diff --git a/package-lock.json b/package-lock.json
index 54a1ea39..7442be64 100644
--- a/package-lock.json
+++ b/package-lock.json
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         "vscode-test": {
-            "version": "1.0.0",
-            "resolved": "https://registry.npmjs.org/vscode-test/-/vscode-test-1.0.0.tgz",
-            "integrity": "sha512-RnZUhxEXYCozHtBAQwX/UISlw0JPqlv1I9LLl4++vcPDIvjs2Zfz2Inp8haxixS1sOTftHJ9kiecrwWF9S3taQ==",
+            "version": "1.2.3",
+            "resolved": "https://registry.npmjs.org/vscode-test/-/vscode-test-1.2.3.tgz",
+            "integrity": "sha512-mKRTNso33NaUULiPBFg6zRjyntjcCpIgkrogyPQuKlvoQREQR8jLKN5UD4L5rkTSD+oBhcKtaLR2/g34FexURw==",
             "dev": true,
             "requires": {
                 "http-proxy-agent": "^2.1.0",
-                "https-proxy-agent": "^2.2.1"
+                "https-proxy-agent": "^2.2.4",
+                "rimraf": "^2.6.3"
             }
         },
         "watchpack": {
@@ -4779,34 +4782,34 @@
             }
         },
         "webpack": {
-            "version": "4.36.1",
-            "resolved": "https://registry.npmjs.org/webpack/-/webpack-4.36.1.tgz",
-            "integrity": "sha512-Ej01/N9W8DVyhEpeQnbUdGvOECw0L46FxS12cCOs8gSK7bhUlrbHRnWkjiXckGlHjUrmL89kDpTRIkUk6Y+fKg==",
+            "version": "4.41.2",
+            "resolved": "https://registry.npmjs.org/webpack/-/webpack-4.41.2.tgz",
+            "integrity": "sha512-Zhw69edTGfbz9/8JJoyRQ/pq8FYUoY0diOXqW0T6yhgdhCv6wr0hra5DwwWexNRns2Z2+gsnrNcbe9hbGBgk/A==",
             "dev": true,
             "requires": {
                 "@webassemblyjs/ast": "1.8.5",
                 "@webassemblyjs/helper-module-context": "1.8.5",
                 "@webassemblyjs/wasm-edit": "1.8.5",
                 "@webassemblyjs/wasm-parser": "1.8.5",
-                "acorn": "^6.2.0",
-                "ajv": "^6.1.0",
-                "ajv-keywords": "^3.1.0",
-                "chrome-trace-event": "^1.0.0",
+                "acorn": "^6.2.1",
+                "ajv": "^6.10.2",
+                "ajv-keywords": "^3.4.1",
+                "chrome-trace-event": "^1.0.2",
                 "enhanced-resolve": "^4.1.0",
-                "eslint-scope": "^4.0.0",
+                "eslint-scope": "^4.0.3",
                 "json-parse-better-errors": "^1.0.2",
-                "loader-runner": "^2.3.0",
-                "loader-utils": "^1.1.0",
-                "memory-fs": "~0.4.1",
-                "micromatch": "^3.1.8",
-                "mkdirp": "~0.5.0",
-                "neo-async": "^2.5.0",
-                "node-libs-browser": "^2.0.0",
+                "loader-runner": "^2.4.0",
+                "loader-utils": "^1.2.3",
+                "memory-fs": "^0.4.1",
+                "micromatch": "^3.1.10",
+                "mkdirp": "^0.5.1",
+                "neo-async": "^2.6.1",
+                "node-libs-browser": "^2.2.1",
                 "schema-utils": "^1.0.0",
-                "tapable": "^1.1.0",
-                "terser-webpack-plugin": "^1.1.0",
-                "watchpack": "^1.5.0",
-                "webpack-sources": "^1.3.0"
+                "tapable": "^1.1.3",
+                "terser-webpack-plugin": "^1.4.1",
+                "watchpack": "^1.6.0",
+                "webpack-sources": "^1.4.1"
             },
             "dependencies": {
                 "braces": {
@@ -5034,9 +5037,9 @@
             }
         },
         "webpack-sources": {
-            "version": "1.3.0",
-            "resolved": "https://registry.npmjs.org/webpack-sources/-/webpack-sources-1.3.0.tgz",
-            "integrity": "sha512-OiVgSrbGu7NEnEvQJJgdSFPl2qWKkWq5lHMhgiToIiN9w34EBnjYzSYs+VbL5KoYiLNtFFa7BZIKxRED3I32pA==",
+            "version": "1.4.3",
+            "resolved": "https://registry.npmjs.org/webpack-sources/-/webpack-sources-1.4.3.tgz",
+            "integrity": "sha512-lgTS3Xhv1lCOKo7SA5TjKXMjpSM4sBjNV5+q2bqesbSPs5FjGmU6jjtBSkX9b4qW87vDIsCIlUPOEhbZrMdjeQ==",
             "dev": true,
             "requires": {
                 "source-list-map": "^2.0.0",
@@ -5150,9 +5153,9 @@
             "dev": true
         },
         "yallist": {
-            "version": "3.0.3",
-            "resolved": "https://registry.npmjs.org/yallist/-/yallist-3.0.3.tgz",
-            "integrity": "sha512-S+Zk8DEWE6oKpV+vI3qWkaK+jSbIK86pCwe2IF/xwIpQ8jEuxpw9NyaGjmp9+BoJv5FV2piqCDcoCtStppiq2A==",
+            "version": "3.1.1",
+            "resolved": "https://registry.npmjs.org/yallist/-/yallist-3.1.1.tgz",
+            "integrity": "sha512-a4UGQaWPH59mOXUYnAG2ewncQS4i4F43Tv3JoAM+s2VDAmS9NsK8GpDMLrCHPksFT7h3K6TOoUNn2pb7RoXx4g==",
             "dev": true
         },
         "yargs": {
diff --git a/package.json b/package.json
index df969592..df56b89c 100644
--- a/package.json
+++ b/package.json
@@ -386,8 +386,9 @@
         "@neilsustc/markdown-it-katex": "^0.4.0",
         "highlight.js": "^9.15.6",
         "image-size": "^0.7.4",
-        "markdown-it": "^8.4.2",
+        "markdown-it-footnote": "^3.0.2",
         "markdown-it-task-lists": "^2.1.1",
+        "markdown-it": "^8.4.2",
         "string-similarity": "^3.0.0"
     },
     "devDependencies": {
@@ -401,7 +402,7 @@
         "mocha": "^6.2.0",
         "ts-loader": "^6.0.4",
         "typescript": "^3.5.2",
-        "vscode-test": "^1.0.0",
+        "vscode-test": "^1.2.3",
         "webpack": "^4.41.2",
         "webpack-cli": "^3.3.6"
     }
diff --git a/src/print.ts b/src/print.ts
index 10dafa2f..0613a9eb 100644
--- a/src/print.ts
+++ b/src/print.ts
@@ -4,10 +4,9 @@
 
 import * as fs from "fs";
 import * as path from 'path';
-import * as vscode from 'vscode';
+import { commands, ExtensionContext, extensions, TextDocument, Uri, window, workspace, WorkspaceConfiguration } from 'vscode';
 import localize from './localize';
 import { isMdEditor, slugify } from './util';
-import { workspace } from 'vscode';
 
 let md;
 let slugCounts = {};
@@ -43,6 +42,12 @@ async function initMdIt() {
         }
     }).use(mdtl).use(mdkt, katexOptions);
 
+    // Conditional modules
+    if (extensions.getExtension('bierner.markdown-footnotes') !== undefined) {
+        const mdfn = await import('markdown-it-footnote');
+        md = md.use(mdfn);
+    }
+
     if (!workspace.getConfiguration('markdown.extension.print').get<boolean>('validateUrls', true)) {
         md.validateLink = () => true;
     }
@@ -77,32 +82,32 @@ function addNamedHeaders(md: any): void {
     };
 }
 
-let thisContext: vscode.ExtensionContext;
+let thisContext: ExtensionContext;
 
-export function activate(context: vscode.ExtensionContext) {
+export function activate(context: ExtensionContext) {
     thisContext = context;
     context.subscriptions.push(
-        vscode.commands.registerCommand('markdown.extension.printToHtml', () => { print('html'); }),
-        vscode.workspace.onDidSaveTextDocument(onDidSave)
+        commands.registerCommand('markdown.extension.printToHtml', () => { print('html'); }),
+        workspace.onDidSaveTextDocument(onDidSave)
     );
 }
 
 export function deactivate() { }
 
-function onDidSave(doc: vscode.TextDocument) {
+function onDidSave(doc: TextDocument) {
     if (
         doc.languageId === 'markdown'
-        && vscode.workspace.getConfiguration('markdown.extension.print', doc.uri).get<boolean>('onFileSave')
+        && workspace.getConfiguration('markdown.extension.print', doc.uri).get<boolean>('onFileSave')
     ) {
         print('html');
     }
 }
 
 async function print(type: string) {
-    const editor = vscode.window.activeTextEditor;
+    const editor = window.activeTextEditor;
 
     if (!isMdEditor(editor)) {
-        vscode.window.showErrorMessage(localize("noValidMarkdownFile"));
+        window.showErrorMessage(localize("noValidMarkdownFile"));
         return;
     }
 
@@ -111,7 +116,7 @@ async function print(type: string) {
         doc.save();
     }
 
-    vscode.window.setStatusBarMessage(localize("printing") + ` '${path.basename(doc.fileName)}' ` + localize("to") + ` '${type.toUpperCase()}' ...`, 1000);
+    window.setStatusBarMessage(localize("printing") + ` '${path.basename(doc.fileName)}' ` + localize("to") + ` '${type.toUpperCase()}' ...`, 1000);
 
     /**
      * Modified from <https://github.com/Microsoft/vscode/tree/master/extensions/markdown>
@@ -130,10 +135,10 @@ async function print(type: string) {
         title = title.replace(/^#+/, '').replace(/#+$/, '').trim();
     }
 
-    let body: string = await render(doc.getText(), vscode.workspace.getConfiguration('markdown.preview', doc.uri));
+    let body: string = await render(doc.getText(), workspace.getConfiguration('markdown.preview', doc.uri));
 
     // Image paths
-    const config = vscode.workspace.getConfiguration('markdown.extension', doc.uri);
+    const config = workspace.getConfiguration('markdown.extension', doc.uri);
     const configToBase64 = config.get<boolean>('print.imgToBase64');
     const configAbsPath = config.get<boolean>('print.absoluteImgPath');
     const imgTagRegex = /(<img[^>]+src=")([^"]+)("[^>]*>)/g;  // Match '<img...src="..."...>'
@@ -150,7 +155,7 @@ async function print(type: string) {
                 const file = fs.readFileSync(imgSrc).toString('base64');
                 return `${p1}data:image/${imgExt};base64,${file}${p3}`;
             } catch (e) {
-                vscode.window.showWarningMessage(localize("unableToReadFile") + ` ${imgSrc}, ` + localize("revertingToImagePaths"));
+                window.showWarningMessage(localize("unableToReadFile") + ` ${imgSrc}, ` + localize("revertingToImagePaths"));
             }
 
             if (configAbsPath) {
@@ -202,7 +207,7 @@ function hasMathEnv(text: string) {
     return text.includes('$');
 }
 
-async function render(text: string, config: vscode.WorkspaceConfiguration) {
+async function render(text: string, config: WorkspaceConfiguration) {
     if (md === undefined) {
         await initMdIt();
     }
@@ -237,12 +242,12 @@ function readCss(fileName: string) {
         msg = msg.replace(/'([c-z]):/, function (_, g1) {
             return `'${g1.toUpperCase()}:`;
         });
-        vscode.window.showWarningMessage(msg);
+        window.showWarningMessage(msg);
         return '';
     }
 }
 
-function getStyles(uri: vscode.Uri, hasMathEnv: boolean) {
+function getStyles(uri: Uri, hasMathEnv: boolean) {
     const katexCss = '<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/katex@0.10.2/dist/katex.min.css" integrity="sha384-yFRtMMDnQtDRO8rLpMIKrtPCD5jdktao2TV19YiZYWMDkUR5GQZR/NOVTdquEx1j" crossorigin="anonymous">';
     const markdownCss = '<link rel="stylesheet" href="https://cdn.jsdelivr.net/gh/Microsoft/vscode/extensions/markdown-language-features/media/markdown.css">';
     const highlightCss = '<link rel="stylesheet" href="https://cdn.jsdelivr.net/gh/Microsoft/vscode/extensions/markdown-language-features/media/highlight.css">';
@@ -260,10 +265,10 @@ function getStyles(uri: vscode.Uri, hasMathEnv: boolean) {
         ${customCssPaths.map(cssSrc => wrapWithStyleTag(cssSrc)).join('\n')}`;
 }
 
-function getCustomStyleSheets(resource: vscode.Uri): string[] {
-    const styles = vscode.workspace.getConfiguration('markdown', resource)['styles'];
+function getCustomStyleSheets(resource: Uri): string[] {
+    const styles = workspace.getConfiguration('markdown', resource)['styles'];
     if (styles && Array.isArray(styles) && styles.length > 0) {
-        const root = vscode.workspace.getWorkspaceFolder(resource);
+        const root = workspace.getWorkspaceFolder(resource);
         return styles.map(s => {
             if (!s || s.startsWith('http') || path.isAbsolute(s)) {
                 return s;
@@ -280,7 +285,7 @@ function getCustomStyleSheets(resource: vscode.Uri): string[] {
     return [];
 }
 
-function relToAbsPath(resource: vscode.Uri, href: string): string {
+function relToAbsPath(resource: Uri, href: string): string {
     if (!href || href.startsWith('http') || path.isAbsolute(href)) {
         return href;
     }
@@ -290,7 +295,7 @@ function relToAbsPath(resource: vscode.Uri, href: string): string {
 }
 
 function getPreviewSettingStyles(): string {
-    const previewSettings = vscode.workspace.getConfiguration('markdown')['preview'];
+    const previewSettings = workspace.getConfiguration('markdown')['preview'];
     if (!previewSettings) {
         return '';
     }