diff --git a/src/css/content.scss b/src/css/content.scss
index 6e63d43b..60d0a41c 100644
--- a/src/css/content.scss
+++ b/src/css/content.scss
@@ -39,6 +39,29 @@ $color-dark-yellow: #DAA520;
 .almost-transparent {
   opacity: 0.1;
 }
+
+.k2-hide-comment-buttons {
+  display: inline-flex;
+  gap: 4px;
+  margin-right: 8px;
+  align-items: center;
+  vertical-align: middle;
+
+  .k2-hide-comment-button {
+    height: 22px;
+    padding: 0 6px;
+    font-size: 12px;
+    line-height: 20px;
+  }
+}
+
+.k2-minimized-comment {
+  padding: 8px 12px;
+  border: 1px solid $color-neutral-light;
+  color: $color-neutral;
+  font-style: italic;
+}
+
 .k2-inactive {
   opacity: 0.2;
 }
diff --git a/src/js/lib/api.js b/src/js/lib/api.js
index 81c95f6c..15619136 100644
--- a/src/js/lib/api.js
+++ b/src/js/lib/api.js
@@ -40,7 +40,7 @@ function getCurrentUser() {
  */
 function getRequestParams() {
     const url = window.location.href;
-    const regex = /github.com\/(?<owner>\w*)\/(?<repo>\w*)(?:\/(?:issues|pull)\/(?<issue_number>\d*))?/;
+    const regex = /github.com\/(?<owner>[\w-]+)\/(?<repo>[\w.-]+)(?:\/(?:issues|pull)\/(?<issue_number>\d+))?/;
     const matches = url.match(regex);
 
     return {
@@ -609,6 +609,66 @@ function updateComment(commentId, body) {
     });
 }
 
+/**
+ * Look up an issue comment's GraphQL node ID by its numeric REST ID.
+ * @param {Number|String} commentID
+ * @returns {Promise<String>}
+ */
+function getIssueCommentNodeID(commentID) {
+    const {owner, repo} = getRequestParams();
+    return getOctokit().rest.issues.getComment({owner, repo, comment_id: Number(commentID)})
+        .then(response => response.data.node_id);
+}
+
+/**
+ * Look up a pull-request review's GraphQL node ID by its numeric REST ID.
+ * @param {Number|String} reviewID
+ * @returns {Promise<String>}
+ */
+function getPullRequestReviewNodeID(reviewID) {
+    const {owner, repo, issue_number} = getRequestParams();
+    return getOctokit().rest.pulls.getReview({
+        owner,
+        repo,
+        pull_number: Number(issue_number),
+        review_id: Number(reviewID),
+    }).then(response => response.data.node_id);
+}
+
+/**
+ * Look up an inline PR review-thread comment's GraphQL node ID by its numeric REST ID.
+ * @param {Number|String} commentID
+ * @returns {Promise<String>}
+ */
+function getPullRequestReviewCommentNodeID(commentID) {
+    const {owner, repo} = getRequestParams();
+    return getOctokit().rest.pulls.getReviewComment({
+        owner,
+        repo,
+        comment_id: Number(commentID),
+    }).then(response => response.data.node_id);
+}
+
+/**
+ * Minimize a comment with a GitHub reported-content classifier.
+ * @param {String} nodeID GraphQL node ID of the comment subject
+ * @param {String} classifier ReportedContentClassifiers enum value
+ * @returns {Promise}
+ */
+function minimizeComment(nodeID, classifier) {
+    const mutation = `
+        mutation MinimizeComment($id: ID!, $classifier: ReportedContentClassifiers!) {
+            minimizeComment(input: {subjectId: $id, classifier: $classifier}) {
+                minimizedComment {
+                    isMinimized
+                    minimizedReason
+                }
+            }
+        }
+    `;
+    return getOctokit().graphql(mutation, {id: nodeID, classifier});
+}
+
 /**
  * Get recent workflow runs for a specific workflow
  * @param {String} workflowId
@@ -658,6 +718,10 @@ export {
     updateComment,
     getWorkflowRuns,
     getWorkflowRun,
+    getIssueCommentNodeID,
+    getPullRequestReviewNodeID,
+    getPullRequestReviewCommentNodeID,
+    minimizeComment,
     getStatusCheckRollup,
     getPullRequestHeadRefOid,
 };
diff --git a/src/js/lib/hideCommentButtons.js b/src/js/lib/hideCommentButtons.js
new file mode 100644
index 00000000..1b0d5f84
--- /dev/null
+++ b/src/js/lib/hideCommentButtons.js
@@ -0,0 +1,258 @@
+import _ from 'underscore';
+import * as API from './api';
+
+const ACTIONS = [
+    {classifier: 'OFF_TOPIC', label: 'Off-topic'},
+    {classifier: 'OUTDATED', label: 'Outdated'},
+    {classifier: 'RESOLVED', label: 'Resolved'},
+];
+
+const BUTTONS_CLASS = 'k2-hide-comment-buttons';
+
+// Author profile links in comment headers use hovercards across GitHub UIs.
+// GitHub App bots use an /apps/ URL instead.
+const AUTHOR_SELECTOR = [
+    '.timeline-comment-header a.author[data-hovercard-type="user"]',
+    '.timeline-comment-header a.author[data-hovercard-url*="/users/"]',
+    '.timeline-comment-header a.author[href*="/apps/"]',
+].join(', ');
+const COMMENT_BODY_SELECTOR = '.comment-body.js-comment-body';
+
+// Match the comment type needed by the REST endpoint that returns its GraphQL node ID.
+// Check review-thread comments before review comments because their URLs overlap.
+const PERMALINK_TYPES = [
+    {type: 'pullrequestreviewcomment', pattern: /pullrequestreviewcomment-(\d+)/},
+    {type: 'pullrequestreviewcomment', pattern: /discussion_r(\d+)/},
+    {type: 'pullrequestreview', pattern: /pullrequestreview-(\d+)/},
+    {type: 'issuecomment', pattern: /issuecomment-(\d+)/},
+];
+const PERMALINK_SELECTOR = [
+    'a[href*="#issuecomment-"]',
+    'a[href*="#pullrequestreview-"]',
+    'a[href*="#pullrequestreviewcomment-"]',
+    'a[href*="#discussion_r"]',
+].join(', ');
+
+let observer = null;
+let scanScheduled = false;
+
+function isOptionsButton(btn) {
+    const label = (btn.getAttribute('aria-label') || '').toLowerCase();
+    if (label.includes('options') || label.includes('show menu') || label === 'more') {
+        return true;
+    }
+
+    return !!btn.querySelector('.octicon-kebab-horizontal, [class*="KebabHorizontal"]');
+}
+
+// The React UI uses a button. The legacy review UI uses a summary element.
+function findOptionsButton(rootEl) {
+    return _.find(rootEl.querySelectorAll('button, summary'), btn => isOptionsButton(btn)) || null;
+}
+
+// Ignore user mentions inside comment bodies because they are not comment authors.
+function isHeaderAuthorLink(link) {
+    const text = (link.textContent || '').trim();
+    if (text.startsWith('@')) {
+        return false;
+    }
+    if (link.classList.contains('user-mention')) {
+        return false;
+    }
+    if (link.closest(COMMENT_BODY_SELECTOR)) {
+        return false;
+    }
+    if (link.closest('.timeline-comment[id^="pullrequest-"]')) {
+        return false;
+    }
+    return true;
+}
+
+function parsePermalink(permalink) {
+    const href = permalink.getAttribute('href') || '';
+    for (let i = 0; i < PERMALINK_TYPES.length; i++) {
+        const {type, pattern} = PERMALINK_TYPES[i];
+        const match = href.match(pattern);
+        if (match) {
+            return {type, id: match[1]};
+        }
+    }
+    return null;
+}
+
+function getPermalinkHash(permalink) {
+    const href = permalink.getAttribute('href') || '';
+    const hashIdx = href.indexOf('#');
+    return hashIdx >= 0 ? href.slice(hashIdx + 1) : '';
+}
+
+// Find the smallest ancestor that contains the author, permalink, and comment body.
+function findCommentHeader(authorLink) {
+    let el = authorLink.parentElement;
+    while (el && el !== document.body) {
+        const permalink = el.querySelector(PERMALINK_SELECTOR);
+        if (permalink) {
+            const parsed = parsePermalink(permalink);
+            if (parsed) {
+                const hash = getPermalinkHash(permalink);
+                const idMatches = hash && (el.id === hash || !!el.querySelector(`[id="${CSS.escape(hash)}"]`));
+                const hasBody = !!el.querySelector(COMMENT_BODY_SELECTOR);
+                if (idMatches || hasBody) {
+                    return {
+                        container: el, permalink, parsed, optionsBtn: findOptionsButton(el),
+                    };
+                }
+            }
+        }
+        el = el.parentElement;
+    }
+    return null;
+}
+
+function getMinimizeForm(wrapper) {
+    const comment = wrapper.closest('.timeline-comment-group');
+    return comment && comment.querySelector('form.js-timeline-comment-minimize');
+}
+
+// Render the same state that GitHub uses when the native form is unavailable.
+function showMinimizedComment(wrapper) {
+    const comment = wrapper.closest('.timeline-comment, .timeline-comment-group');
+    const body = comment && comment.querySelector(COMMENT_BODY_SELECTOR);
+    if (!comment || !body) {
+        return;
+    }
+
+    const header = comment.querySelector('.timeline-comment-header');
+    const bodyContainer = body.closest('.edit-comment-hide') || body;
+    if (header) {
+        header.style.display = 'none';
+    }
+    bodyContainer.style.display = 'none';
+    comment.classList.remove('unminimized-comment');
+    comment.classList.add('minimized-comment', 'position-relative');
+
+    const minimized = document.createElement('div');
+    minimized.className = 'k2-minimized-comment';
+    minimized.textContent = body.textContent.trim() || 'This comment has been minimized.';
+    comment.appendChild(minimized);
+}
+
+function lookupNodeID(commentType, commentID) {
+    if (commentType === 'pullrequestreview') {
+        return API.getPullRequestReviewNodeID(commentID);
+    }
+    if (commentType === 'pullrequestreviewcomment') {
+        return API.getPullRequestReviewCommentNodeID(commentID);
+    }
+    return API.getIssueCommentNodeID(commentID);
+}
+
+function setButtonsDisabled(wrapper, disabled) {
+    _.each(wrapper.querySelectorAll('button'), (button) => {
+        if (disabled) {
+            button.setAttribute('disabled', 'disabled');
+        } else {
+            button.removeAttribute('disabled');
+        }
+    });
+}
+
+async function minimizeComment(event) {
+    const button = event.currentTarget;
+    const wrapper = button.closest(`.${BUTTONS_CLASS}`);
+    const commentID = wrapper && wrapper.dataset.commentId;
+    const commentType = wrapper && wrapper.dataset.commentType;
+    const classifier = button.dataset.classifier;
+    if (!commentID || !commentType || !classifier) {
+        return;
+    }
+    setButtonsDisabled(wrapper, true);
+    const form = getMinimizeForm(wrapper);
+    if (form) {
+        const select = form.querySelector('select[name="classifier"]');
+        if (select) {
+            select.value = classifier;
+            form.requestSubmit();
+            return;
+        }
+    }
+    try {
+        const nodeID = await lookupNodeID(commentType, commentID);
+        await API.minimizeComment(nodeID, classifier);
+        showMinimizedComment(wrapper);
+    } catch (error) {
+        setButtonsDisabled(wrapper, false);
+        wrapper.title = error instanceof Error ? error.message : 'Failed to hide comment';
+    }
+}
+
+function addButtons({
+    container, permalink, parsed, optionsBtn,
+}) {
+    if (container.querySelector(`.${BUTTONS_CLASS}`)) {
+        return;
+    }
+
+    // A review can render more than one author link. Prevent duplicate button groups.
+    if (document.querySelector(`.${BUTTONS_CLASS}[data-comment-id="${CSS.escape(parsed.id)}"][data-comment-type="${CSS.escape(parsed.type)}"]`)) {
+        return;
+    }
+
+    const wrapper = document.createElement('span');
+    wrapper.className = `${BUTTONS_CLASS} k2-element`;
+    wrapper.dataset.commentId = parsed.id;
+    wrapper.dataset.commentType = parsed.type;
+    _.each(ACTIONS, (action) => {
+        const btn = document.createElement('button');
+        btn.type = 'button';
+        btn.className = 'btn btn-sm k2-hide-comment-button';
+        btn.dataset.classifier = action.classifier;
+        btn.textContent = action.label;
+        btn.addEventListener('click', minimizeComment);
+        wrapper.appendChild(btn);
+    });
+
+    // Place buttons before the kebab when GitHub exposes the action menu.
+    if (optionsBtn) {
+        const anchor = optionsBtn;
+        const target = anchor.tagName === 'SUMMARY' ? (anchor.closest('details') || anchor) : anchor;
+        target.parentNode.insertBefore(wrapper, target);
+    } else {
+        permalink.parentNode.insertBefore(wrapper, permalink.nextSibling);
+    }
+}
+
+function scan() {
+    _.each(document.querySelectorAll(AUTHOR_SELECTOR), (authorLink) => {
+        if (!isHeaderAuthorLink(authorLink)) {
+            return;
+        }
+        const header = findCommentHeader(authorLink);
+        if (!header) {
+            return;
+        }
+        addButtons(header);
+    });
+}
+
+function scheduleScan() {
+    if (scanScheduled) {
+        return;
+    }
+    scanScheduled = true;
+    requestAnimationFrame(() => {
+        scanScheduled = false;
+        scan();
+    });
+}
+
+function initHideCommentButtons() {
+    if (observer) {
+        return;
+    }
+    scheduleScan();
+    observer = new MutationObserver(scheduleScan);
+    observer.observe(document.body, {childList: true, subtree: true});
+}
+
+export default initHideCommentButtons;
diff --git a/src/js/lib/pages/github/issue.js b/src/js/lib/pages/github/issue.js
index 7076739f..8e308c8c 100644
--- a/src/js/lib/pages/github/issue.js
+++ b/src/js/lib/pages/github/issue.js
@@ -14,6 +14,7 @@ import K2previousissues from '../../../module/K2previousissues/K2previousissues'
 import ONYXKEYS from '../../../ONYXKEYS';
 import * as API from '../../api';
 import * as autoLoadMoreComments from '../../autoLoadMoreComments';
+import hideCommentButtons from '../../hideCommentButtons';
 
 let clearErrorTimeoutID;
 function catchError(e) {
@@ -231,6 +232,7 @@ export default function () {
         setInterval(() => IssuePage.renderPaymentDetailsButton(), 2000);
 
         autoLoadMoreComments.initAutoLoadMoreComments();
+        hideCommentButtons();
     };
 
     return IssuePage;
diff --git a/src/js/lib/pages/github/pr.js b/src/js/lib/pages/github/pr.js
index 1cc7b031..fd03ecce 100644
--- a/src/js/lib/pages/github/pr.js
+++ b/src/js/lib/pages/github/pr.js
@@ -3,6 +3,7 @@ import Base from './_base';
 import ToggleTimestamps from '../../../module/ToggleTimestamps/ToggleTimestamps';
 import ToggleAutoLoadMore from '../../../module/ToggleAutoLoadMore/ToggleAutoLoadMore';
 import * as autoLoadMoreComments from '../../autoLoadMoreComments';
+import hideCommentButtons from '../../hideCommentButtons';
 import * as commitCheckStatuses from '../../commitCheckStatuses';
 import * as prFavicon from '../../prFavicon';
 
@@ -146,10 +147,10 @@ export default function () {
         setInterval(() => PrPage.renderTranslationWorkflowButtons(), 2000);
 
         autoLoadMoreComments.initAutoLoadMoreComments();
+        hideCommentButtons();
         commitCheckStatuses.initCommitCheckStatuses();
         prFavicon.initPrFavicon();
     };
 
     return PrPage;
 }
-