diff --git a/app/assets/javascripts/quote_reply.js b/app/assets/javascripts/quote_reply.js
deleted file mode 100644
index dd05d27fe..000000000
--- a/app/assets/javascripts/quote_reply.js
+++ /dev/null
@@ -1,224 +0,0 @@
-import { Controller } from '@hotwired/stimulus'
-import TurndownService from 'turndown'
-import { post } from '@rails/request.js'
-
-class QuoteExtractor {
-  static extract(targetElement) {
-    return new QuoteExtractor(targetElement).extract();
-  }
-
-  constructor(targetElement) {
-    this.targetElement = targetElement;
-    this.selection = window.getSelection();
-  }
-
-  extract() {
-    const range = this.retriveSelectedRange();
-
-    if (!range) {
-      return null;
-    }
-
-    if (!this.targetElement.contains(range.startContainer)) {
-      range.setStartBefore(this.targetElement);
-    }
-    if (!this.targetElement.contains(range.endContainer)) {
-      range.setEndAfter(this.targetElement);
-    }
-
-    return range;
-  }
-
-  retriveSelectedRange() {
-    if (!this.isSelected) {
-      return null;
-    }
-
-    // Retrive the first range that intersects with the target element.
-    // NOTE: Firefox allows to select multiple ranges in the document.
-    for (let i = 0; i < this.selection.rangeCount; i++) {
-      let range = this.selection.getRangeAt(i);
-      if (range.intersectsNode(this.targetElement)) {
-        return range;
-      }
-    }
-    return null;
-  }
-
-  get isSelected() {
-    return this.selection.containsNode(this.targetElement, true);
-  }
-}
-
-class QuoteTextFormatter {
-  format(selectedRange) {
-    if (!selectedRange) {
-      return null;
-    }
-
-    const fragment = document.createElement('div');
-    fragment.appendChild(selectedRange.cloneContents());
-
-    // Remove all unnecessary anchor elements
-    fragment.querySelectorAll('a.wiki-anchor').forEach(e => e.remove());
-
-    const html = this.adjustLineBreaks(fragment.innerHTML);
-
-    const result = document.createElement('div');
-    result.innerHTML = html;
-
-    // Replace continuous line breaks with a single line break and remove tab characters
-    return result.textContent
-      .trim()
-      .replace(/\t/g, '')
-      .replace(/\n+/g, "\n");
-  }
-
-  adjustLineBreaks(html) {
-    return html
-      .replace(/<\/(h1|h2|h3|h4|div|p|li|tr)>/g, "\n</$1>")
-      .replace(/<br>/g, "\n")
-  }
-}
-
-class QuoteCommonMarkFormatter {
-  format(selectedRange) {
-    if (!selectedRange) {
-      return null;
-    }
-
-    const htmlFragment = this.extractHtmlFragmentFrom(selectedRange);
-    const preparedHtml = this.prepareHtml(htmlFragment);
-
-    return this.convertHtmlToCommonMark(preparedHtml);
-  }
-
-  extractHtmlFragmentFrom(range) {
-    const fragment = document.createElement('div');
-    const ancestorNodeName = range.commonAncestorContainer.nodeName;
-
-    if (ancestorNodeName == 'CODE' || ancestorNodeName == '#text') {
-      fragment.appendChild(this.wrapPreCode(range));
-    } else {
-      fragment.appendChild(range.cloneContents());
-    }
-
-    return fragment;
-  }
-
-  // When only the content within the `<code>` element is selected,
-  // the HTML within the selection range does not include the `<pre><code>` element itself.
-  // To create a complete code block, wrap the selected content with the `<pre><code>` tags.
-  //
-  // selected contentes => <pre><code class="ruby">selected contents</code></pre>
-  wrapPreCode(range) {
-    const rangeAncestor = range.commonAncestorContainer;
-
-    let codeElement = null;
-
-    if (rangeAncestor.nodeName == 'CODE') {
-      codeElement = rangeAncestor;
-    } else {
-      codeElement = rangeAncestor.parentElement.closest('code');
-    }
-
-    if (!codeElement) {
-      return range.cloneContents();
-    }
-
-    const pre = document.createElement('pre');
-    const code = codeElement.cloneNode(false);
-
-    code.appendChild(range.cloneContents());
-    pre.appendChild(code);
-
-    return pre;
-  }
-
-  convertHtmlToCommonMark(html) {
-    const turndownService = new TurndownService({
-      codeBlockStyle: 'fenced',
-      headingStyle: 'atx'
-    });
-
-    turndownService.addRule('del', {
-      filter: ['del'],
-      replacement: content => `~~${content}~~`
-    });
-
-    turndownService.addRule('checkList', {
-      filter: node => {
-        return node.type === 'checkbox' && node.parentNode.nodeName === 'LI';
-      },
-      replacement: (content, node) => {
-        return node.checked ? '[x]' : '[ ]';
-      }
-    });
-
-    // Table does not maintain its original format,
-    // and the text within the table is displayed as it is
-    //
-    // | A | B | C |
-    // |---|---|---|
-    // | 1 | 2 | 3 |
-    // =>
-    // A B C
-    // 1 2 3
-    turndownService.addRule('table', {
-      filter: ['td', 'th'],
-      replacement: (content, node) => {
-        const separator = node.parentElement.lastElementChild === node ? '' : ' ';
-        return content + separator;
-      }
-    });
-    turndownService.addRule('tableHeading', {
-      filter: ['thead', 'tbody', 'tfoot', 'tr'],
-      replacement: (content, _node) => content
-    });
-    turndownService.addRule('tableRow', {
-      filter: ['tr'],
-      replacement: (content, _node) => {
-        return content + '\n'
-      }
-    });
-
-    return turndownService.turndown(html);
-  }
-
-  prepareHtml(htmlFragment) {
-    // Remove all anchor elements.
-    // <h1>Title1<a href="#Title" class="wiki-anchor">¶</a></h1> => <h1>Title1</h1>
-    htmlFragment.querySelectorAll('a.wiki-anchor').forEach(e => e.remove());
-
-    // Convert code highlight blocks to CommonMark format code blocks.
-    // <code class="ruby" data-language="ruby"> => <code class="language-ruby" data-language="ruby">
-    htmlFragment.querySelectorAll('code[data-language]').forEach(e => {
-      e.classList.replace(e.dataset['language'], 'language-' + e.dataset['language'])
-    });
-
-    return htmlFragment.innerHTML;
-  }
-}
-
-export default class extends Controller {
-  static targets = [ 'content' ];
-
-  quote(event) {
-    const { url, textFormatting } = event.params;
-    const selectedRange = QuoteExtractor.extract(this.contentTarget);
-
-    let formatter;
-
-    if (textFormatting === 'common_mark') {
-      formatter = new QuoteCommonMarkFormatter();
-    } else {
-      formatter = new QuoteTextFormatter();
-    }
-
-    post(url, {
-      body: JSON.stringify({ quote: formatter.format(selectedRange) }),
-      contentType: 'application/json',
-      responseKind: 'script'
-    });
-  }
-}
diff --git a/app/assets/javascripts/turndown-7.2.0.min.js b/app/assets/javascripts/turndown-7.2.0.min.js
deleted file mode 100644
index e69de29bb..000000000