Fix rebase merge issues.

Author: KlausLoeffelmann

src/System.Windows.Forms/System/Windows/Forms/Form.cs

@@ -2183,6 +2183,7 @@ protected override void SetVisibleCore(bool value)
     [SRDescription(nameof(SR.FormCornerPreferenceDescr))]
     [Browsable(false)]
     [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
+    [Experimental(DiagnosticIDs.ExperimentalDarkMode, UrlFormat = DiagnosticIDs.UrlFormat)]
     public FormCornerPreference FormCornerPreference
     {
         get => Properties.GetValueOrDefault(s_propFormCornerPreference, FormCornerPreference.Default);
@@ -2220,6 +2221,7 @@ public FormCornerPreference FormCornerPreference
     /// <param name="e">
     ///  An <see cref="EventArgs"/> that contains the event data, in this case empty.
     /// </param>
+    [Experimental(DiagnosticIDs.ExperimentalDarkMode, UrlFormat = DiagnosticIDs.UrlFormat)]
     protected virtual void OnFormCornerPreferenceChanged(EventArgs e)
     {
         if (Events[s_formCornerPreferenceChanged] is EventHandler eventHandler)
@@ -2228,6 +2230,7 @@ protected virtual void OnFormCornerPreferenceChanged(EventArgs e)
         }
     }
 
+#pragma warning disable WFO5001 // Type is for evaluation purposes only and is subject to change or removal in future updates. Suppress this diagnostic to proceed.
     private unsafe void SetFormCornerPreferenceInternal(FormCornerPreference cornerPreference)
     {
         DWM_WINDOW_CORNER_PREFERENCE dwmCornerPreference = cornerPreference switch
@@ -2245,6 +2248,7 @@ private unsafe void SetFormCornerPreferenceInternal(FormCornerPreference cornerP
             &dwmCornerPreference,
             sizeof(DWM_WINDOW_CORNER_PREFERENCE));
     }
+#pragma warning restore WFO5001 // Type is for evaluation purposes only and is subject to change or removal in future updates. Suppress this diagnostic to proceed.
 
     /// <summary>
     ///  Sets or gets the Form's border color.
@@ -2271,6 +2275,7 @@ private unsafe void SetFormCornerPreferenceInternal(FormCornerPreference cornerP
     [SRDescription(nameof(SR.FormBorderColorDescr))]
     [Browsable(false)]
     [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
+    [Experimental(DiagnosticIDs.ExperimentalDarkMode, UrlFormat = DiagnosticIDs.UrlFormat)]
     public Color FormBorderColor
     {
         get => Properties.GetValueOrDefault(s_propFormBorderColor, Color.Empty);
@@ -2298,6 +2303,7 @@ public Color FormBorderColor
     /// <param name="e">
     ///  An <see cref="EventArgs"/> that contains the event data, in this case empty.
     /// </param>
+    [Experimental(DiagnosticIDs.ExperimentalDarkMode, UrlFormat = DiagnosticIDs.UrlFormat)]
     protected virtual void OnFormBorderColorChanged(EventArgs e)
     {
         if (Events[s_formBorderColorChanged] is EventHandler eventHandler)
@@ -2331,6 +2337,7 @@ protected virtual void OnFormBorderColorChanged(EventArgs e)
     [SRDescription(nameof(SR.FormCaptionBackColorDescr))]
     [Browsable(false)]
     [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
+    [Experimental(DiagnosticIDs.ExperimentalDarkMode, UrlFormat = DiagnosticIDs.UrlFormat)]
     public Color FormCaptionBackColor
     {
         get => Properties.GetValueOrDefault(s_propFormCaptionBackColor, Color.Empty);
@@ -2359,6 +2366,7 @@ public Color FormCaptionBackColor
     /// <param name="e">
     ///  An <see cref="EventArgs"/> that contains the event data, in this case empty.
     /// </param>
+    [Experimental(DiagnosticIDs.ExperimentalDarkMode, UrlFormat = DiagnosticIDs.UrlFormat)]
     protected virtual void OnFormCaptionBackColorChanged(EventArgs e)
     {
         if (Events[s_formCaptionBackColorChanged] is EventHandler eventHandler)
@@ -2392,6 +2400,7 @@ protected virtual void OnFormCaptionBackColorChanged(EventArgs e)
     [SRDescription(nameof(SR.FormCaptionTextColorDescr))]
     [Browsable(false)]
     [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
+    [Experimental(DiagnosticIDs.ExperimentalDarkMode, UrlFormat = DiagnosticIDs.UrlFormat)]
     public Color FormCaptionTextColor
     {
         get => Properties.GetValueOrDefault(s_propFormCaptionTextColor, Color.Empty);
@@ -2420,6 +2429,7 @@ public Color FormCaptionTextColor
     /// <param name="e">
     ///  An <see cref="EventArgs"/> that contains the event data, in this case empty.
     /// </param>
+    [Experimental(DiagnosticIDs.ExperimentalDarkMode, UrlFormat = DiagnosticIDs.UrlFormat)]
     protected virtual void OnFormCaptionTextColorChanged(EventArgs e)
     {
         if (Events[s_formCaptionTextColorChanged] is EventHandler eventHandler)
@@ -4899,10 +4909,12 @@ private void SetFormTitleProperties()
                 SetFormAttributeColorInternal(DWMWINDOWATTRIBUTE.DWMWA_TEXT_COLOR, formCaptionTextColor.Value);
             }
 
+#pragma warning disable WFO5001 // Type is for evaluation purposes only and is subject to change or removal in future updates. Suppress this diagnostic to proceed.
             if (Properties.TryGetValue(s_propFormCornerPreference, out FormCornerPreference? cornerPreference))
             {
                 SetFormCornerPreferenceInternal(cornerPreference.Value);
             }
+#pragma warning restore WFO5001 // Type is for evaluation purposes only and is subject to change or removal in future updates. Suppress this diagnostic to proceed.
         }
     }
 

src/System.Windows.Forms/System/Windows/Forms/FormCornerPreference.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Windows.Forms.Analyzers.Diagnostics;
 using Windows.Win32.Graphics.Dwm;
 
 namespace System.Windows.Forms;
@@ -9,6 +10,7 @@ namespace System.Windows.Forms;
 ///  Specifies the corner preference for a <see cref="Form"/> which can be
 ///  set using the <see cref="Form.FormCornerPreference"/> property.
 /// </summary>
+[Experimental(DiagnosticIDs.ExperimentalDarkMode, UrlFormat = DiagnosticIDs.UrlFormat)]
 public enum FormCornerPreference
 {
     /// <summary>