Add sub and sup Markdown tags.

package.json

@@ -37,6 +37,8 @@
     "markdown-it": "^10.0.0",
     "markdown-it-container": "^2.0.0",
     "markdown-it-emoji": "^1.4.0",
+    "markdown-it-sub": "^1.0.0",
+    "markdown-it-sup": "^1.0.0",
     "moment": "^2.24.0",
     "node-fetch": "^2.6.0",
     "prettier": "^2.0.4",

src/components/markdown-textarea.tsx

@@ -469,6 +469,16 @@ export class MarkdownTextArea extends Component<
     i.simpleInsert('#');
   }
 
+  handleInsertSubscript(i: MarkdownTextArea, event: any) {
+    event.preventDefault();
+    i.simpleInsert('~');
+  }
+
+  handleInsertSuperscript(i: MarkdownTextArea, event: any) {
+    event.preventDefault();
+    i.simpleInsert('^');
+  }
+
   simpleInsert(chars: string) {
     if (!this.state.content) {
       this.state.content = `${chars} `;

src/utils.ts

@@ -49,6 +49,8 @@ import { UserService, WebSocketService } from './services';
 
 import Tribute from 'tributejs/src/Tribute.js';
 import markdown_it from 'markdown-it';
+import markdown_it_sub from 'markdown-it-sub';
+import markdown_it_sup from 'markdown-it-sup';
 import markdownitEmoji from 'markdown-it-emoji/light';
 import markdown_it_container from 'markdown-it-container';
 import emojiShortName from 'emoji-short-name';
@@ -148,6 +150,8 @@ export const md = new markdown_it({
   linkify: true,
   typographer: true,
 })
+  .use(markdown_it_sub)
+  .use(markdown_it_sup)
   .use(markdown_it_container, 'spoiler', {
     validate: function (params: any) {
       return params.trim().match(/^spoiler\s+(.*)$/);

yarn.lock

@@ -4317,6 +4317,16 @@ [email protected]^1.4.0:
   resolved "https://registry.yarnpkg.com/markdown-it-emoji/-/markdown-it-emoji-1.4.0.tgz#9bee0e9a990a963ba96df6980c4fddb05dfb4dcc"
   integrity sha1-m+4OmpkKljupbfaYDE/dsF37Tcw=
 
+[email protected]^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/markdown-it-sub/-/markdown-it-sub-1.0.0.tgz#375fd6026eae7ddcb012497f6411195ea1e3afe8"
+  integrity sha1-N1/WAm6ufdywEkl/ZBEZXqHjr+g=
+
+[email protected]^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/markdown-it-sup/-/markdown-it-sup-1.0.0.tgz#cb9c9ff91a5255ac08f3fd3d63286e15df0a1fc3"
+  integrity sha1-y5yf+RpSVawI8/09YyhuFd8KH8M=
+
 [email protected]^10.0.0:
   version "10.0.0"
   resolved "https://registry.yarnpkg.com/markdown-it/-/markdown-it-10.0.0.tgz#abfc64f141b1722d663402044e43927f1f50a8dc"