feat: replace browser scroll with esl scrollbar

src/plugins/editor/editor.less

@@ -1,4 +1,5 @@
 .uip-editor {
+  position: relative;
   grid-area: editor;
   display: block;
   max-height: 325px;

src/plugins/editor/editor.tsx

@@ -36,6 +36,8 @@ export class UIPEditor extends UIPPlugin {
   /** Initialize inner {@link https://medv.io/codejar/ Codejar} editor */
   protected initEditor(): void {
     const codeBlock = (<pre class='language-html editor-content'><code/></pre>) as HTMLPreElement;
+    this.$inner.classList.add('esl-scrollable-content');
+    this.$inner.append(<esl-scrollbar target="::parent"></esl-scrollbar> as HTMLElement);
     this.$inner.append(codeBlock);
 
     this.editor = new JarEditor(codeBlock, this.editorConfig);

src/plugins/settings/settings.tsx

@@ -32,7 +32,7 @@ export class UIPSettings extends UIPPlugin {
     const $content = <div className="settings-list esl-scrollable-content">
       <esl-scrollbar target="::prev(.settings-list)"></esl-scrollbar>
     </div>;
-$content.append(...this.childNodes);
+    $content.append(...this.childNodes);
     this.$inner.appendChild($content);
     this.appendChild(this.$inner);
   }