diff --git a/Essay_Analysis_Tool/DiffViewerForm.Designer.cs b/Essay_Analysis_Tool/DiffViewerForm.Designer.cs
new file mode 100644
index 0000000..3af60df
--- /dev/null
+++ b/Essay_Analysis_Tool/DiffViewerForm.Designer.cs
@@ -0,0 +1,303 @@
+namespace Essay_Analysis_Tool
+{
+    partial class DiffViewerForm
+    {
+        /// <summary>
+        /// Required designer variable.
+        /// </summary>
+        private System.ComponentModel.IContainer components = null;
+
+        /// <summary>
+        /// Clean up any resources being used.
+        /// </summary>
+        /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+        protected override void Dispose(bool disposing)
+        {
+            if (disposing && (components != null))
+            {
+                components.Dispose();
+            }
+            base.Dispose(disposing);
+        }
+
+        #region Windows Form Designer generated code
+
+        /// <summary>
+        /// Required method for Designer support - do not modify
+        /// the contents of this method with the code editor.
+        /// </summary>
+        private void InitializeComponent()
+        {
+            this.components = new System.ComponentModel.Container();
+            System.ComponentModel.ComponentResourceManager resources = new System.ComponentModel.ComponentResourceManager(typeof(DiffViewerForm));
+            this.label6 = new System.Windows.Forms.Label();
+            this.label7 = new System.Windows.Forms.Label();
+            this.label5 = new System.Windows.Forms.Label();
+            this.label4 = new System.Windows.Forms.Label();
+            this.label3 = new System.Windows.Forms.Label();
+            this.tbSecondFile = new System.Windows.Forms.TextBox();
+            this.btSecond = new System.Windows.Forms.Button();
+            this.label2 = new System.Windows.Forms.Label();
+            this.tbFirstFile = new System.Windows.Forms.TextBox();
+            this.btFirst = new System.Windows.Forms.Button();
+            this.ofdFile = new System.Windows.Forms.OpenFileDialog();
+            this.btCompare = new System.Windows.Forms.Button();
+            this.fctb1 = new FastColoredTextBoxNS.FastColoredTextBox();
+            this.fctb2 = new FastColoredTextBoxNS.FastColoredTextBox();
+            this.splitContainer1 = new System.Windows.Forms.SplitContainer();
+            ((System.ComponentModel.ISupportInitialize)(this.fctb1)).BeginInit();
+            ((System.ComponentModel.ISupportInitialize)(this.fctb2)).BeginInit();
+            ((System.ComponentModel.ISupportInitialize)(this.splitContainer1)).BeginInit();
+            this.splitContainer1.Panel1.SuspendLayout();
+            this.splitContainer1.Panel2.SuspendLayout();
+            this.splitContainer1.SuspendLayout();
+            this.SuspendLayout();
+            // 
+            // label6
+            // 
+            this.label6.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)));
+            this.label6.AutoSize = true;
+            this.label6.Location = new System.Drawing.Point(136, 415);
+            this.label6.Name = "label6";
+            this.label6.Size = new System.Drawing.Size(68, 13);
+            this.label6.TabIndex = 24;
+            this.label6.Text = "Deleted lines";
+            // 
+            // label7
+            // 
+            this.label7.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)));
+            this.label7.BackColor = System.Drawing.Color.Pink;
+            this.label7.Location = new System.Drawing.Point(118, 415);
+            this.label7.Name = "label7";
+            this.label7.Size = new System.Drawing.Size(12, 13);
+            this.label7.TabIndex = 23;
+            this.label7.Text = " ";
+            // 
+            // label5
+            // 
+            this.label5.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)));
+            this.label5.AutoSize = true;
+            this.label5.Location = new System.Drawing.Point(30, 415);
+            this.label5.Name = "label5";
+            this.label5.Size = new System.Drawing.Size(69, 13);
+            this.label5.TabIndex = 22;
+            this.label5.Text = "Inserted lines";
+            // 
+            // label4
+            // 
+            this.label4.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)));
+            this.label4.BackColor = System.Drawing.Color.PaleGreen;
+            this.label4.Location = new System.Drawing.Point(12, 415);
+            this.label4.Name = "label4";
+            this.label4.Size = new System.Drawing.Size(12, 13);
+            this.label4.TabIndex = 21;
+            this.label4.Text = " ";
+            // 
+            // label3
+            // 
+            this.label3.AutoSize = true;
+            this.label3.Location = new System.Drawing.Point(13, 40);
+            this.label3.Name = "label3";
+            this.label3.Size = new System.Drawing.Size(60, 13);
+            this.label3.TabIndex = 20;
+            this.label3.Text = "Second file";
+            // 
+            // tbSecondFile
+            // 
+            this.tbSecondFile.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left) 
+            | System.Windows.Forms.AnchorStyles.Right)));
+            this.tbSecondFile.Location = new System.Drawing.Point(79, 37);
+            this.tbSecondFile.Name = "tbSecondFile";
+            this.tbSecondFile.Size = new System.Drawing.Size(497, 20);
+            this.tbSecondFile.TabIndex = 19;
+            // 
+            // btSecond
+            // 
+            this.btSecond.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right)));
+            this.btSecond.Location = new System.Drawing.Point(582, 34);
+            this.btSecond.Name = "btSecond";
+            this.btSecond.Size = new System.Drawing.Size(30, 23);
+            this.btSecond.TabIndex = 18;
+            this.btSecond.Text = "...";
+            this.btSecond.UseVisualStyleBackColor = true;
+            this.btSecond.Click += new System.EventHandler(this.SelectSecondFileButton_Click);
+            // 
+            // label2
+            // 
+            this.label2.AutoSize = true;
+            this.label2.Location = new System.Drawing.Point(31, 13);
+            this.label2.Name = "label2";
+            this.label2.Size = new System.Drawing.Size(42, 13);
+            this.label2.TabIndex = 17;
+            this.label2.Text = "First file";
+            // 
+            // tbFirstFile
+            // 
+            this.tbFirstFile.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left) 
+            | System.Windows.Forms.AnchorStyles.Right)));
+            this.tbFirstFile.Location = new System.Drawing.Point(79, 11);
+            this.tbFirstFile.Name = "tbFirstFile";
+            this.tbFirstFile.Size = new System.Drawing.Size(497, 20);
+            this.tbFirstFile.TabIndex = 16;
+            // 
+            // btFirst
+            // 
+            this.btFirst.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right)));
+            this.btFirst.Location = new System.Drawing.Point(582, 8);
+            this.btFirst.Name = "btFirst";
+            this.btFirst.Size = new System.Drawing.Size(30, 23);
+            this.btFirst.TabIndex = 15;
+            this.btFirst.Text = "...";
+            this.btFirst.UseVisualStyleBackColor = true;
+            this.btFirst.Click += new System.EventHandler(this.SelectFirstFileButton_Click);
+            // 
+            // btCompare
+            // 
+            this.btCompare.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right)));
+            this.btCompare.Location = new System.Drawing.Point(537, 63);
+            this.btCompare.Name = "btCompare";
+            this.btCompare.Size = new System.Drawing.Size(75, 23);
+            this.btCompare.TabIndex = 25;
+            this.btCompare.Text = "Compare";
+            this.btCompare.UseVisualStyleBackColor = true;
+            this.btCompare.Click += new System.EventHandler(this.CompareButton_Click);
+            // 
+            // fctb1
+            // 
+            this.fctb1.AutoCompleteBracketsList = new char[] {
+        '(',
+        ')',
+        '{',
+        '}',
+        '[',
+        ']',
+        '\"',
+        '\"',
+        '\'',
+        '\''};
+            this.fctb1.AutoIndentCharsPatterns = "^\\s*[\\w\\.]+(\\s\\w+)?\\s*(?<range>=)\\s*(?<range>[^;=]+);\n^\\s*(case|default)\\s*[^:]*(" +
+    "?<range>:)\\s*(?<range>[^;]+);";
+            this.fctb1.AutoScrollMinSize = new System.Drawing.Size(27, 14);
+            this.fctb1.BackBrush = null;
+            this.fctb1.CharHeight = 14;
+            this.fctb1.CharWidth = 8;
+            this.fctb1.Cursor = System.Windows.Forms.Cursors.IBeam;
+            this.fctb1.DisabledColor = System.Drawing.Color.FromArgb(((int)(((byte)(100)))), ((int)(((byte)(180)))), ((int)(((byte)(180)))), ((int)(((byte)(180)))));
+            this.fctb1.Dock = System.Windows.Forms.DockStyle.Fill;
+            this.fctb1.IsReplaceMode = false;
+            this.fctb1.Location = new System.Drawing.Point(0, 0);
+            this.fctb1.Name = "fctb1";
+            this.fctb1.Paddings = new System.Windows.Forms.Padding(0);
+            this.fctb1.ReadOnly = true;
+            this.fctb1.SelectionColor = System.Drawing.Color.FromArgb(((int)(((byte)(60)))), ((int)(((byte)(0)))), ((int)(((byte)(0)))), ((int)(((byte)(255)))));
+            this.fctb1.ServiceColors = ((FastColoredTextBoxNS.ServiceColors)(resources.GetObject("fctb1.ServiceColors")));
+            this.fctb1.Size = new System.Drawing.Size(342, 311);
+            this.fctb1.TabIndex = 26;
+            this.fctb1.Zoom = 100;
+            this.fctb1.SelectionChanged += new System.EventHandler(this.FastColoredTextBox_VisibleRangeChanged);
+            this.fctb1.VisibleRangeChanged += new System.EventHandler(this.FastColoredTextBox_VisibleRangeChanged);
+            // 
+            // fctb2
+            // 
+            this.fctb2.AutoCompleteBracketsList = new char[] {
+        '(',
+        ')',
+        '{',
+        '}',
+        '[',
+        ']',
+        '\"',
+        '\"',
+        '\'',
+        '\''};
+            this.fctb2.AutoIndentCharsPatterns = "^\\s*[\\w\\.]+(\\s\\w+)?\\s*(?<range>=)\\s*(?<range>[^;=]+);\n^\\s*(case|default)\\s*[^:]*(" +
+    "?<range>:)\\s*(?<range>[^;]+);";
+            this.fctb2.AutoScrollMinSize = new System.Drawing.Size(27, 14);
+            this.fctb2.BackBrush = null;
+            this.fctb2.CharHeight = 14;
+            this.fctb2.CharWidth = 8;
+            this.fctb2.Cursor = System.Windows.Forms.Cursors.IBeam;
+            this.fctb2.DisabledColor = System.Drawing.Color.FromArgb(((int)(((byte)(100)))), ((int)(((byte)(180)))), ((int)(((byte)(180)))), ((int)(((byte)(180)))));
+            this.fctb2.Dock = System.Windows.Forms.DockStyle.Fill;
+            this.fctb2.IsReplaceMode = false;
+            this.fctb2.Location = new System.Drawing.Point(0, 0);
+            this.fctb2.Name = "fctb2";
+            this.fctb2.Paddings = new System.Windows.Forms.Padding(0);
+            this.fctb2.ReadOnly = true;
+            this.fctb2.SelectionColor = System.Drawing.Color.FromArgb(((int)(((byte)(60)))), ((int)(((byte)(0)))), ((int)(((byte)(0)))), ((int)(((byte)(255)))));
+            this.fctb2.ServiceColors = ((FastColoredTextBoxNS.ServiceColors)(resources.GetObject("fctb2.ServiceColors")));
+            this.fctb2.Size = new System.Drawing.Size(352, 311);
+            this.fctb2.TabIndex = 27;
+            this.fctb2.Zoom = 100;
+            this.fctb2.SelectionChanged += new System.EventHandler(this.FastColoredTextBox_VisibleRangeChanged);
+            this.fctb2.VisibleRangeChanged += new System.EventHandler(this.FastColoredTextBox_VisibleRangeChanged);
+            // 
+            // splitContainer1
+            // 
+            this.splitContainer1.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom) 
+            | System.Windows.Forms.AnchorStyles.Left) 
+            | System.Windows.Forms.AnchorStyles.Right)));
+            this.splitContainer1.Location = new System.Drawing.Point(12, 92);
+            this.splitContainer1.Name = "splitContainer1";
+            // 
+            // splitContainer1.Panel1
+            // 
+            this.splitContainer1.Panel1.Controls.Add(this.fctb1);
+            // 
+            // splitContainer1.Panel2
+            // 
+            this.splitContainer1.Panel2.Controls.Add(this.fctb2);
+            this.splitContainer1.Size = new System.Drawing.Size(698, 311);
+            this.splitContainer1.SplitterDistance = 342;
+            this.splitContainer1.TabIndex = 28;
+            // 
+            // DiffViewerForm
+            // 
+            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
+            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
+            this.ClientSize = new System.Drawing.Size(722, 437);
+            this.Controls.Add(this.splitContainer1);
+            this.Controls.Add(this.btCompare);
+            this.Controls.Add(this.label6);
+            this.Controls.Add(this.label7);
+            this.Controls.Add(this.label5);
+            this.Controls.Add(this.label4);
+            this.Controls.Add(this.label3);
+            this.Controls.Add(this.tbSecondFile);
+            this.Controls.Add(this.btSecond);
+            this.Controls.Add(this.label2);
+            this.Controls.Add(this.tbFirstFile);
+            this.Controls.Add(this.btFirst);
+            this.Name = "DiffViewerForm";
+            this.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen;
+            this.Text = "Diff Viewer";
+            ((System.ComponentModel.ISupportInitialize)(this.fctb1)).EndInit();
+            ((System.ComponentModel.ISupportInitialize)(this.fctb2)).EndInit();
+            this.splitContainer1.Panel1.ResumeLayout(false);
+            this.splitContainer1.Panel2.ResumeLayout(false);
+            ((System.ComponentModel.ISupportInitialize)(this.splitContainer1)).EndInit();
+            this.splitContainer1.ResumeLayout(false);
+            this.ResumeLayout(false);
+            this.PerformLayout();
+
+        }
+
+        #endregion
+
+        private System.Windows.Forms.Label label6;
+        private System.Windows.Forms.Label label7;
+        private System.Windows.Forms.Label label5;
+        private System.Windows.Forms.Label label4;
+        private System.Windows.Forms.Label label3;
+        private System.Windows.Forms.TextBox tbSecondFile;
+        private System.Windows.Forms.Button btSecond;
+        private System.Windows.Forms.Label label2;
+        private System.Windows.Forms.TextBox tbFirstFile;
+        private System.Windows.Forms.Button btFirst;
+        private System.Windows.Forms.OpenFileDialog ofdFile;
+        private System.Windows.Forms.Button btCompare;
+        private FastColoredTextBoxNS.FastColoredTextBox fctb1;
+        private FastColoredTextBoxNS.FastColoredTextBox fctb2;
+        private System.Windows.Forms.SplitContainer splitContainer1;
+    }
+}
\ No newline at end of file
diff --git a/Essay_Analysis_Tool/DiffViewerForm.cs b/Essay_Analysis_Tool/DiffViewerForm.cs
new file mode 100644
index 0000000..379b091
--- /dev/null
+++ b/Essay_Analysis_Tool/DiffViewerForm.cs
@@ -0,0 +1,585 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Drawing;
+using System.IO;
+using System.Text;
+using System.Windows.Forms;
+using Essay_Analysis_Tool.DiffMergeStuffs;
+using FastColoredTextBoxNS;
+
+namespace Essay_Analysis_Tool
+{
+    public partial class DiffViewerForm : Form
+    {
+        private int _updating;
+        private static readonly Style _greenStyle;
+        private static readonly Style _redStyle;
+
+        static DiffViewerForm()
+        {
+            _greenStyle = new MarkerStyle(new SolidBrush(Color.FromArgb(50, Color.Lime)));
+            _redStyle = new MarkerStyle(new SolidBrush(Color.FromArgb(50, Color.Red)));
+        }
+
+        public DiffViewerForm()
+            : this("") { }
+
+        /// <summary>
+        /// Initialize a new form.
+        /// </summary>
+        /// <param name="file">Absolute or relative file path.</param>
+        public DiffViewerForm(string file)
+            : this(file, "") { }
+
+        /// <summary>
+        /// Initialize a new form.
+        /// </summary>
+        /// <param name="file1">Absolute or relative file path.</param>
+        /// <param name="file2">Absolute or relative file path.</param>
+        public DiffViewerForm(string file1, string file2)
+        {
+            InitializeComponent();
+
+            tbFirstFile.Text = file1;
+            tbSecondFile.Text = file2;
+        }
+
+        private void SelectFirstFileButton_Click(object sender, EventArgs e)
+        {
+            if (ofdFile.ShowDialog() == DialogResult.OK)
+                tbFirstFile.Text = ofdFile.FileName;
+        }
+
+        private void SelectSecondFileButton_Click(object sender, EventArgs e)
+        {
+            if (ofdFile.ShowDialog() == DialogResult.OK)
+                tbSecondFile.Text = ofdFile.FileName;
+        }
+
+        private void CompareButton_Click(object sender, EventArgs e)
+        {
+            if (!File.Exists(tbFirstFile.Text) || !File.Exists(tbSecondFile.Text))
+            {
+                MessageBox.Show(this, "Please select a valid file", "Invalid file");
+                return;
+            }
+
+            fctb1.Clear();
+            fctb2.Clear();
+
+            Cursor = Cursors.WaitCursor;
+
+            if (Path.GetExtension(tbFirstFile.Text).ToLower() == ".cs")
+                fctb1.Language = fctb2.Language = Language.CSharp;
+            else
+                fctb1.Language = fctb2.Language = Language.Custom;
+
+            var source1 = Lines.Load(tbFirstFile.Text);
+            var source2 = Lines.Load(tbSecondFile.Text);
+
+            source1.Merge(source2);
+
+            BeginUpdate();
+
+            Process(source1);
+
+            EndUpdate();
+
+            Cursor = Cursors.Default;
+        }
+
+        private void FastColoredTextBox_VisibleRangeChanged(object sender, EventArgs e)
+        {
+            if (_updating > 0)
+                return;
+
+            var vPos = (sender as FastColoredTextBox).VerticalScroll.Value;
+            var curLine = (sender as FastColoredTextBox).Selection.Start.iLine;
+
+            if (sender == fctb2)
+                UpdateScroll(fctb1, vPos, curLine);
+            else
+                UpdateScroll(fctb2, vPos, curLine);
+
+            fctb1.Refresh();
+            fctb2.Refresh();
+        }
+
+        private void UpdateScroll(FastColoredTextBox tb, int vPos, int curLine)
+        {
+            if (_updating > 0)
+                return;
+            //
+            BeginUpdate();
+            //
+            if (vPos <= tb.VerticalScroll.Maximum)
+            {
+                tb.VerticalScroll.Value = vPos;
+                tb.UpdateScrollbars();
+            }
+
+            if (curLine < tb.LinesCount)
+                tb.Selection = new Range(tb, 0, curLine, 0, curLine);
+            //
+            EndUpdate();
+        }
+
+        private void EndUpdate()
+        {
+            _updating--;
+        }
+
+        private void BeginUpdate()
+        {
+            _updating++;
+        }
+
+        private void Process(Lines lines)
+        {
+            foreach (var line in lines)
+            {
+                switch (line.state)
+                {
+                    case DiffType.None:
+                        fctb1.AppendText(line.line + Environment.NewLine);
+                        fctb2.AppendText(line.line + Environment.NewLine);
+                        break;
+                    case DiffType.Inserted:
+                        fctb1.AppendText(Environment.NewLine);
+                        fctb2.AppendText(line.line + Environment.NewLine, _greenStyle);
+                        break;
+                    case DiffType.Deleted:
+                        fctb1.AppendText(line.line + Environment.NewLine, _redStyle);
+                        fctb2.AppendText(Environment.NewLine);
+                        break;
+                }
+                if (line.subLines != null)
+                    Process(line.subLines);
+            }
+        }
+    }
+
+    #region Merge stuffs
+
+    namespace DiffMergeStuffs
+    {
+        public class SimpleDiff<T>
+        {
+            private IList<T> _left;
+            private IList<T> _right;
+            private int[,] _matrix;
+            private bool _matrixCreated;
+            private int _preSkip;
+            private int _postSkip;
+
+            private Func<T, T, bool> _compareFunc;
+
+            public SimpleDiff(IList<T> left, IList<T> right)
+            {
+                _left = left;
+                _right = right;
+
+                InitializeCompareFunc();
+            }
+
+            public event EventHandler<DiffEventArgs<T>> LineUpdate;
+
+            public TimeSpan ElapsedTime { get; private set; }
+
+            /// <summary>
+            /// This is the sole public method and it initializes
+            /// the LCS matrix the first time it's called, and 
+            /// proceeds to fire a series of LineUpdate events
+            /// </summary>
+            public void RunDiff()
+            {
+                if (!_matrixCreated)
+                {
+                    Stopwatch sw = new Stopwatch();
+                    sw.Start();
+                    CalculatePreSkip();
+                    CalculatePostSkip();
+                    CreateLCSMatrix();
+                    sw.Stop();
+                    this.ElapsedTime = sw.Elapsed;
+                }
+
+                for (int i = 0; i < _preSkip; i++)
+                {
+                    FireLineUpdate(DiffType.None, i, -1);
+                }
+
+                int totalSkip = _preSkip + _postSkip;
+                ShowDiff(_left.Count - totalSkip, _right.Count - totalSkip);
+
+                int leftLen = _left.Count;
+                for (int i = _postSkip; i > 0; i--)
+                {
+                    FireLineUpdate(DiffType.None, leftLen - i, -1);
+                }
+            }
+
+            /// <summary>
+            /// This method is an optimization that
+            /// skips matching elements at the end of the 
+            /// two arrays being diff'ed.
+            /// Care's taken so that this will never
+            /// overlap with the pre-skip.
+            /// </summary>
+            private void CalculatePostSkip()
+            {
+                int leftLen = _left.Count;
+                int rightLen = _right.Count;
+                while (_postSkip < leftLen && _postSkip < rightLen &&
+                       _postSkip < (leftLen - _preSkip) &&
+                       _compareFunc(_left[leftLen - _postSkip - 1], _right[rightLen - _postSkip - 1]))
+                {
+                    _postSkip++;
+                }
+            }
+
+            /// <summary>
+            /// This method is an optimization that
+            /// skips matching elements at the start of
+            /// the arrays being diff'ed
+            /// </summary>
+            private void CalculatePreSkip()
+            {
+                int leftLen = _left.Count;
+                int rightLen = _right.Count;
+                while (_preSkip < leftLen && _preSkip < rightLen &&
+                       _compareFunc(_left[_preSkip], _right[_preSkip]))
+                {
+                    _preSkip++;
+                }
+            }
+
+            /// <summary>
+            /// This traverses the elements using the LCS matrix
+            /// and fires appropriate events for added, subtracted, 
+            /// and unchanged lines.
+            /// It's recursively called till we run out of items.
+            /// </summary>
+            /// <param name="leftIndex"></param>
+            /// <param name="rightIndex"></param>
+            private void ShowDiff(int leftIndex, int rightIndex)
+            {
+                if (leftIndex > 0 && rightIndex > 0 &&
+                    _compareFunc(_left[_preSkip + leftIndex - 1], _right[_preSkip + rightIndex - 1]))
+                {
+                    ShowDiff(leftIndex - 1, rightIndex - 1);
+                    FireLineUpdate(DiffType.None, _preSkip + leftIndex - 1, -1);
+                }
+                else
+                {
+                    if (rightIndex > 0 &&
+                        (leftIndex == 0 ||
+                         _matrix[leftIndex, rightIndex - 1] >= _matrix[leftIndex - 1, rightIndex]))
+                    {
+                        ShowDiff(leftIndex, rightIndex - 1);
+                        FireLineUpdate(DiffType.Inserted, -1, _preSkip + rightIndex - 1);
+                    }
+                    else if (leftIndex > 0 &&
+                             (rightIndex == 0 ||
+                              _matrix[leftIndex, rightIndex - 1] < _matrix[leftIndex - 1, rightIndex]))
+                    {
+                        ShowDiff(leftIndex - 1, rightIndex);
+                        FireLineUpdate(DiffType.Deleted, _preSkip + leftIndex - 1, -1);
+                    }
+                }
+
+            }
+
+            /// <summary>
+            /// This is the core method in the entire class,
+            /// and uses the standard LCS calculation algorithm.
+            /// </summary>
+            private void CreateLCSMatrix()
+            {
+                int totalSkip = _preSkip + _postSkip;
+                if (totalSkip >= _left.Count || totalSkip >= _right.Count)
+                    return;
+
+                // We only create a matrix large enough for the
+                // unskipped contents of the diff'ed arrays
+                _matrix = new int[_left.Count - totalSkip + 1, _right.Count - totalSkip + 1];
+
+                for (int i = 1; i <= _left.Count - totalSkip; i++)
+                {
+                    // Simple optimization to avoid this calculation
+                    // inside the outer loop (may have got JIT optimized 
+                    // but my tests showed a minor improvement in speed)
+                    int leftIndex = _preSkip + i - 1;
+
+                    // Again, instead of calculating the adjusted index inside
+                    // the loop, I initialize it under the assumption that
+                    // incrementing will be a faster operation on most CPUs
+                    // compared to addition. Again, this may have got JIT
+                    // optimized but my tests showed a minor speed difference.
+                    for (int j = 1, rightIndex = _preSkip + 1; j <= _right.Count - totalSkip; j++, rightIndex++)
+                    {
+                        _matrix[i, j] = _compareFunc(_left[leftIndex], _right[rightIndex - 1])
+                                            ? _matrix[i - 1, j - 1] + 1
+                                            : Math.Max(_matrix[i, j - 1], _matrix[i - 1, j]);
+                    }
+                }
+
+                _matrixCreated = true;
+            }
+
+            private void FireLineUpdate(DiffType diffType, int leftIndex, int rightIndex)
+            {
+                var local = this.LineUpdate;
+
+                if (local == null)
+                    return;
+
+                T lineValue = leftIndex >= 0 ? _left[leftIndex] : _right[rightIndex];
+
+                local(this, new DiffEventArgs<T>(diffType, lineValue, leftIndex, rightIndex));
+            }
+
+            private void InitializeCompareFunc()
+            {
+                // Special case for String types
+                if (typeof(T) == typeof(String))
+                {
+                    _compareFunc = StringCompare;
+                }
+                else
+                {
+                    _compareFunc = DefaultCompare;
+                }
+            }
+
+            /// <summary>
+            /// This comparison is specifically
+            /// for strings, and was nearly thrice as 
+            /// fast as the default comparison operation.
+            /// </summary>
+            /// <param name="left"></param>
+            /// <param name="right"></param>
+            /// <returns></returns>
+            private bool StringCompare(T left, T right)
+            {
+                return Object.Equals(left, right);
+            }
+
+            private bool DefaultCompare(T left, T right)
+            {
+                return left.Equals(right);
+            }
+        }
+
+        [Flags]
+        public enum DiffType
+        {
+            None = 0,
+            Inserted = 1,
+            Deleted = 2
+        }
+
+        public class DiffEventArgs<T> : EventArgs
+        {
+            public DiffType DiffType { get; set; }
+
+            public T LineValue { get; private set; }
+            public int LeftIndex { get; private set; }
+            public int RightIndex { get; private set; }
+
+            public DiffEventArgs(DiffType diffType, T lineValue, int leftIndex, int rightIndex)
+            {
+                this.DiffType = diffType;
+                this.LineValue = lineValue;
+                this.LeftIndex = leftIndex;
+                this.RightIndex = rightIndex;
+            }
+        }
+
+        /// <summary>
+        /// Line of file
+        /// </summary>
+        public class Line
+        {
+            /// <summary>
+            /// Source string
+            /// </summary>
+            public readonly string line;
+
+            /// <summary>
+            /// Inserted strings
+            /// </summary>
+            public Lines subLines;
+
+            /// <summary>
+            /// Line state
+            /// </summary>
+            public DiffType state;
+
+            public Line(string line)
+            {
+                this.line = line;
+            }
+
+            /// <summary>
+            /// Equals
+            /// </summary>
+            public override bool Equals(object obj)
+            {
+                return Object.Equals(line, ((Line)obj).line);
+            }
+
+            public static bool operator ==(Line line1, Line line2)
+            {
+                return Object.Equals(line1.line, line2.line);
+            }
+
+            public static bool operator !=(Line line1, Line line2)
+            {
+                return !Object.Equals(line1.line, line2.line);
+            }
+
+            public override string ToString()
+            {
+                return line;
+            }
+        }
+
+        /// <summary>
+        /// File as list of lines.
+        /// </summary>
+        public class Lines : List<Line>, IEquatable<Lines>
+        {
+            private Line fictiveLine = new Line("===fictive line===") { state = DiffType.Deleted };
+
+            public Lines() { }
+            
+            public Lines(int capacity)
+                : base(capacity) { }
+
+            public Line this[int i]
+            {
+                get
+                {
+                    if (i == -1) return fictiveLine;
+                    return base[i];
+                }
+
+                set
+                {
+                    if (i == -1) fictiveLine = value;
+                    base[i] = value;
+                }
+            }
+
+            /// <summary>
+            /// Load from file
+            /// </summary>
+            public static Lines Load(string fileName, Encoding enc = null)
+            {
+                Lines lines = new Lines();
+                foreach (var line in File.ReadAllLines(fileName, enc ?? Encoding.Default))
+                    lines.Add(new Line(line));
+
+                return lines;
+            }
+
+            /// <summary>
+            /// Merge lines
+            /// </summary>
+            public void Merge(Lines lines)
+            {
+                SimpleDiff<Line> diff = new SimpleDiff<Line>(this, lines);
+                int iLine = -1;
+
+                diff.LineUpdate += (o, e) =>
+                {
+                    if (e.DiffType == DiffType.Inserted)
+                    {
+                        if (this[iLine].subLines == null)
+                            this[iLine].subLines = new Lines();
+                        e.LineValue.state = DiffType.Inserted;
+                        this[iLine].subLines.Add(e.LineValue);
+                    }
+                    else
+                    {
+                        iLine++;
+                        this[iLine].state = e.DiffType;
+                        if (iLine > 0 &&
+                            this[iLine - 1].state == DiffType.Deleted &&
+                            this[iLine - 1].subLines == null &&
+                            e.DiffType == DiffType.None)
+                            this[iLine - 1].subLines = new Lines();
+                    }
+                };
+
+                diff.RunDiff();
+            }
+
+            /// <summary>
+            /// Clone
+            /// </summary>
+            public Lines Clone()
+            {
+                Lines result = new Lines(this.Count);
+                foreach (var line in this)
+                    result.Add(new Line(line.line));
+
+                return result;
+            }
+
+            /// <summary>
+            /// Is lines equal?
+            /// </summary>
+            public bool Equals(Lines other)
+            {
+                if (Count != other.Count)
+                    return false;
+                for (int i = 0; i < Count; i++)
+                    if (this[i] != other[i])
+                        return false;
+                return true;
+            }
+
+            /// <summary>
+            /// Transform tree to list
+            /// </summary>
+            public Lines Expand()
+            {
+                return Expand(-1, Count - 1);
+            }
+
+            /// <summary>
+            /// Transform tree to list
+            /// </summary>
+            public Lines Expand(int from, int to)
+            {
+                Lines result = new Lines();
+                for (int i = from; i <= to; i++)
+                {
+                    if (this[i].state != DiffType.Deleted)
+                        result.Add(this[i]);
+                    if (this[i].subLines != null)
+                        result.AddRange(this[i].subLines.Expand());
+                }
+
+                return result;
+            }
+        }
+
+        public class ConflictedLine : Line
+        {
+            public readonly Lines version1;
+            public readonly Lines version2;
+
+            public ConflictedLine(Lines version1, Lines version2)
+                : base("?")
+            {
+                this.version1 = version1;
+                this.version2 = version2;
+            }
+        }
+    }
+    #endregion
+}
\ No newline at end of file
diff --git a/Essay_Analysis_Tool/DiffViewerForm.resx b/Essay_Analysis_Tool/DiffViewerForm.resx
new file mode 100644
index 0000000..1089076
--- /dev/null
+++ b/Essay_Analysis_Tool/DiffViewerForm.resx
@@ -0,0 +1,159 @@
+<?xml version="1.0" encoding="utf-8"?>
+<root>
+  <!-- 
+    Microsoft ResX Schema 
+    
+    Version 2.0
+    
+    The primary goals of this format is to allow a simple XML format 
+    that is mostly human readable. The generation and parsing of the 
+    various data types are done through the TypeConverter classes 
+    associated with the data types.
+    
+    Example:
+    
+    ... ado.net/XML headers & schema ...
+    <resheader name="resmimetype">text/microsoft-resx</resheader>
+    <resheader name="version">2.0</resheader>
+    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>
+    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>
+    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>
+    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>
+    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">
+        <value>[base64 mime encoded serialized .NET Framework object]</value>
+    </data>
+    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
+        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
+        <comment>This is a comment</comment>
+    </data>
+                
+    There are any number of "resheader" rows that contain simple 
+    name/value pairs.
+    
+    Each data row contains a name, and value. The row also contains a 
+    type or mimetype. Type corresponds to a .NET class that support 
+    text/value conversion through the TypeConverter architecture. 
+    Classes that don't support this are serialized and stored with the 
+    mimetype set.
+    
+    The mimetype is used for serialized objects, and tells the 
+    ResXResourceReader how to depersist the object. This is currently not 
+    extensible. For a given mimetype the value must be set accordingly:
+    
+    Note - application/x-microsoft.net.object.binary.base64 is the format 
+    that the ResXResourceWriter will generate, however the reader can 
+    read any of the formats listed below.
+    
+    mimetype: application/x-microsoft.net.object.binary.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
+            : and then encoded with base64 encoding.
+    
+    mimetype: application/x-microsoft.net.object.soap.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
+            : and then encoded with base64 encoding.
+
+    mimetype: application/x-microsoft.net.object.bytearray.base64
+    value   : The object must be serialized into a byte array 
+            : using a System.ComponentModel.TypeConverter
+            : and then encoded with base64 encoding.
+    -->
+  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
+    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />
+    <xsd:element name="root" msdata:IsDataSet="true">
+      <xsd:complexType>
+        <xsd:choice maxOccurs="unbounded">
+          <xsd:element name="metadata">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" />
+              </xsd:sequence>
+              <xsd:attribute name="name" use="required" type="xsd:string" />
+              <xsd:attribute name="type" type="xsd:string" />
+              <xsd:attribute name="mimetype" type="xsd:string" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="assembly">
+            <xsd:complexType>
+              <xsd:attribute name="alias" type="xsd:string" />
+              <xsd:attribute name="name" type="xsd:string" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="data">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />
+              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />
+              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="resheader">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" />
+            </xsd:complexType>
+          </xsd:element>
+        </xsd:choice>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:schema>
+  <resheader name="resmimetype">
+    <value>text/microsoft-resx</value>
+  </resheader>
+  <resheader name="version">
+    <value>2.0</value>
+  </resheader>
+  <resheader name="reader">
+    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <resheader name="writer">
+    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <metadata name="ofdFile.TrayLocation" type="System.Drawing.Point, System.Drawing, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a">
+    <value>17, 17</value>
+  </metadata>
+  <data name="fctb1.ServiceColors" mimetype="application/x-microsoft.net.object.binary.base64">
+    <value>
+        AAEAAAD/////AQAAAAAAAAAMAgAAAFdGYXN0Q29sb3JlZFRleHRCb3gsIFZlcnNpb249Mi4xNi4yNi4w
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+        CgAAAAAAAAAAjQABAAH4/////P///woAAAAAAAAAAKQAAQAB9/////z///8KAAAAAAAAAACWAAEACw==
+</value>
+  </data>
+  <data name="fctb2.ServiceColors" mimetype="application/x-microsoft.net.object.binary.base64">
+    <value>
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+        YXdpbmcuQ29sb3IEAAAABG5hbWUFdmFsdWUKa25vd25Db2xvcgVzdGF0ZQEAAAAJBwcDAAAACgAAAAAA
+        AAAAlgABAAH7/////P///woAAAAAAAAAAKQAAQAB+v////z///8KAAAAAAAAAACWAAEAAfn////8////
+        CgAAAAAAAAAAjQABAAH4/////P///woAAAAAAAAAAKQAAQAB9/////z///8KAAAAAAAAAACWAAEACw==
+</value>
+  </data>
+</root>
\ No newline at end of file
diff --git a/Essay_Analysis_Tool/MainForm.Designer.cs b/Essay_Analysis_Tool/MainForm.Designer.cs
index 4512489..0a868a4 100644
--- a/Essay_Analysis_Tool/MainForm.Designer.cs
+++ b/Essay_Analysis_Tool/MainForm.Designer.cs
@@ -98,6 +98,7 @@ private void InitializeComponent()
             this.tsFiles = new FarsiLibrary.Win.FATabStrip();
             this.documentMap1 = new FastColoredTextBoxNS.DocumentMap();
             this.documentMap = new FastColoredTextBoxNS.DocumentMap();
+            this.diffToolStripMenuItem = new System.Windows.Forms.ToolStripMenuItem();
             this.menuStrip1.SuspendLayout();
             this.statusStrip1.SuspendLayout();
             this.tsMain.SuspendLayout();
@@ -255,7 +256,8 @@ private void InitializeComponent()
             this.statusBarToolStripMenuItem,
             this.syntaxHighlightingToolStripMenuItem,
             this.documentMapToolStripMenuItem,
-            this.loggerToolStripMenuItem});
+            this.loggerToolStripMenuItem,
+            this.diffToolStripMenuItem});
             this.documentMapToolStripItem.Name = "documentMapToolStripItem";
             this.documentMapToolStripItem.Size = new System.Drawing.Size(44, 20);
             this.documentMapToolStripItem.Text = "View";
@@ -264,7 +266,7 @@ private void InitializeComponent()
             // 
             this.statusBarToolStripMenuItem.CheckOnClick = true;
             this.statusBarToolStripMenuItem.Name = "statusBarToolStripMenuItem";
-            this.statusBarToolStripMenuItem.Size = new System.Drawing.Size(178, 22);
+            this.statusBarToolStripMenuItem.Size = new System.Drawing.Size(180, 22);
             this.statusBarToolStripMenuItem.Text = "Status Bar";
             this.statusBarToolStripMenuItem.Click += new System.EventHandler(this.StatusBarToolStripMenuItem_Click);
             // 
@@ -281,7 +283,7 @@ private void InitializeComponent()
             this.visualBasicToolStripMenuItem,
             this.xMLToolStripMenuItem});
             this.syntaxHighlightingToolStripMenuItem.Name = "syntaxHighlightingToolStripMenuItem";
-            this.syntaxHighlightingToolStripMenuItem.Size = new System.Drawing.Size(178, 22);
+            this.syntaxHighlightingToolStripMenuItem.Size = new System.Drawing.Size(180, 22);
             this.syntaxHighlightingToolStripMenuItem.Text = "Syntax Highlighting";
             // 
             // noneToolStripMenuItem
@@ -350,14 +352,14 @@ private void InitializeComponent()
             // documentMapToolStripMenuItem
             // 
             this.documentMapToolStripMenuItem.Name = "documentMapToolStripMenuItem";
-            this.documentMapToolStripMenuItem.Size = new System.Drawing.Size(178, 22);
+            this.documentMapToolStripMenuItem.Size = new System.Drawing.Size(180, 22);
             this.documentMapToolStripMenuItem.Text = "Document Map";
             this.documentMapToolStripMenuItem.Click += new System.EventHandler(this.DocumentMapToolStripMenuItem_Click);
             // 
             // loggerToolStripMenuItem
             // 
             this.loggerToolStripMenuItem.Name = "loggerToolStripMenuItem";
-            this.loggerToolStripMenuItem.Size = new System.Drawing.Size(178, 22);
+            this.loggerToolStripMenuItem.Size = new System.Drawing.Size(180, 22);
             this.loggerToolStripMenuItem.Text = "Logger";
             this.loggerToolStripMenuItem.Click += new System.EventHandler(this.LoggerToolStripMenuItem_Click);
             // 
@@ -644,6 +646,13 @@ private void InitializeComponent()
             this.documentMap.Text = "documentMap";
             this.documentMap.Visible = false;
             // 
+            // diffToolStripMenuItem
+            // 
+            this.diffToolStripMenuItem.Name = "diffToolStripMenuItem";
+            this.diffToolStripMenuItem.Size = new System.Drawing.Size(180, 22);
+            this.diffToolStripMenuItem.Text = "Diff";
+            this.diffToolStripMenuItem.Click += new System.EventHandler(this.DiffToolStripMenuItem_Click);
+            // 
             // MainForm
             // 
             this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
@@ -731,6 +740,7 @@ private void InitializeComponent()
         private System.Windows.Forms.ToolStripButton hlCurrentLineToolStripButton;
         private System.Windows.Forms.ImageList imageList1;
         private System.Windows.Forms.ToolStripMenuItem loggerToolStripMenuItem;
+        private System.Windows.Forms.ToolStripMenuItem diffToolStripMenuItem;
     }
 }
 
diff --git a/Essay_Analysis_Tool/MainForm.cs b/Essay_Analysis_Tool/MainForm.cs
index 2d78935..bb9a44b 100644
--- a/Essay_Analysis_Tool/MainForm.cs
+++ b/Essay_Analysis_Tool/MainForm.cs
@@ -970,6 +970,31 @@ private void SanitizeTabStrip()
             }
         }
 
+        private bool IsSavedTab(string tagName) => tagName != null;
+
+        private void DiffToolStripMenuItem_Click(object sender, EventArgs e)
+        {
+            List<string> filePaths = new List<string>();
+
+            foreach (FATabStripItem item in tsFiles.Items)
+            {
+                string filePath = (string)item.Tag;
+
+                if (IsSavedTab(filePath))
+                    filePaths.Add(filePath);
+
+                    if (filePaths.Count == 2)
+                        break;
+            }
+
+            if  (filePaths.Count == 1)
+                new DiffViewerForm(filePaths[0]).Show();
+            else if (filePaths.Count == 2)
+                new DiffViewerForm(filePaths[0], filePaths[1]).Show();
+            else
+                new DiffViewerForm().Show();
+        }
+
         #endregion
 
         #region Document Map Functionality
diff --git a/Essay_Analysis_Tool/MainForm.resx b/Essay_Analysis_Tool/MainForm.resx
index dd40328..2cb6045 100644
--- a/Essay_Analysis_Tool/MainForm.resx
+++ b/Essay_Analysis_Tool/MainForm.resx
@@ -133,48 +133,48 @@
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diff --git a/Essay_Analysis_Tool/Notepad-Sharp.csproj b/Essay_Analysis_Tool/Notepad-Sharp.csproj
index a62fa62..b75d559 100644
--- a/Essay_Analysis_Tool/Notepad-Sharp.csproj
+++ b/Essay_Analysis_Tool/Notepad-Sharp.csproj
@@ -55,6 +55,12 @@
     </Reference>
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="DiffViewerForm.cs">
+      <SubType>Form</SubType>
+    </Compile>
+    <Compile Include="DiffViewerForm.Designer.cs">
+      <DependentUpon>DiffViewerForm.cs</DependentUpon>
+    </Compile>
     <Compile Include="LoggerMessageTypeEnum.cs" />
     <Compile Include="LoggerForm.cs">
       <SubType>Form</SubType>
@@ -70,6 +76,9 @@
     </Compile>
     <Compile Include="Program.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
+    <EmbeddedResource Include="DiffViewerForm.resx">
+      <DependentUpon>DiffViewerForm.cs</DependentUpon>
+    </EmbeddedResource>
     <EmbeddedResource Include="LoggerForm.resx">
       <DependentUpon>LoggerForm.cs</DependentUpon>
     </EmbeddedResource>
diff --git a/Essay_Analysis_Tool/changes.xml b/Essay_Analysis_Tool/changes.xml
index 6847fef..f78eefb 100644
--- a/Essay_Analysis_Tool/changes.xml
+++ b/Essay_Analysis_Tool/changes.xml
@@ -3,6 +3,7 @@
   <body>
     <release date="${buildTimestamp}" description="" version="1.0.0">
       <action dev="" issue="" date="" type=""></action>
+      <action dev="Tom PoLáKoSz" issue="ISSUE-0065" date="19-09-2019" type="add">Implement diffmerge feature.</action>
       <action dev="Zachary Pedigo" issue="ISSUE-0084" date="09-09-2019" type="fix">Changing language causes CurrentTB changed flag to be set to true.</action>
       <action dev="Zachary Pedigo" issue="ISSUE-0082" date="09-09-2019" type="fix">Editor does not recognize .vbs extension.</action>
       <action dev="Tom PoLáKoSz" issue="ISSUE-0089" date="08-29-2019" type="fix">App crashes when clicking File/Open submenu after fresh start.</action>