diff --git a/polygerrit-ui/app/behaviors/keyboard-shortcut-behavior/keyboard-shortcut-behavior.js b/polygerrit-ui/app/behaviors/keyboard-shortcut-behavior/keyboard-shortcut-behavior.js
index 09e3b7264e..ca31ee80b0 100644
--- a/polygerrit-ui/app/behaviors/keyboard-shortcut-behavior/keyboard-shortcut-behavior.js
+++ b/polygerrit-ui/app/behaviors/keyboard-shortcut-behavior/keyboard-shortcut-behavior.js
@@ -171,6 +171,7 @@ const Shortcut = {
   TOGGLE_FILE_REVIEWED: 'TOGGLE_FILE_REVIEWED',
   TOGGLE_ALL_INLINE_DIFFS: 'TOGGLE_ALL_INLINE_DIFFS',
   TOGGLE_INLINE_DIFF: 'TOGGLE_INLINE_DIFF',
+  TOGGLE_HIDE_ALL_COMMENT_THREADS: 'TOGGLE_HIDE_ALL_COMMENT_THREADS',
 
   OPEN_FIRST_FILE: 'OPEN_FIRST_FILE',
   OPEN_LAST_FILE: 'OPEN_LAST_FILE',
@@ -251,6 +252,8 @@ _describe(Shortcut.EXPAND_ALL_COMMENT_THREADS, ShortcutSection.DIFFS,
     'Expand all comment threads');
 _describe(Shortcut.COLLAPSE_ALL_COMMENT_THREADS, ShortcutSection.DIFFS,
     'Collapse all comment threads');
+_describe(Shortcut.TOGGLE_HIDE_ALL_COMMENT_THREADS, ShortcutSection.DIFFS,
+    'Hide/Display all comment threads');
 _describe(Shortcut.LEFT_PANE, ShortcutSection.DIFFS, 'Select left pane');
 _describe(Shortcut.RIGHT_PANE, ShortcutSection.DIFFS, 'Select right pane');
 _describe(Shortcut.TOGGLE_LEFT_PANE, ShortcutSection.DIFFS,
@@ -290,6 +293,8 @@ _describe(Shortcut.OPEN_FILE, ShortcutSection.FILE_LIST,
     'Go to selected file');
 _describe(Shortcut.TOGGLE_ALL_INLINE_DIFFS, ShortcutSection.FILE_LIST,
     'Show/hide all inline diffs');
+_describe(Shortcut.TOGGLE_HIDE_ALL_COMMENT_THREADS, ShortcutSection.FILE_LIST,
+    'Hide/Display all comment threads');
 _describe(Shortcut.TOGGLE_INLINE_DIFF, ShortcutSection.FILE_LIST,
     'Show/hide selected inline diff');
 
diff --git a/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.js b/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.js
index 5e9825a2de..a0d4d42c0a 100644
--- a/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.js
+++ b/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.js
@@ -275,6 +275,8 @@ class GrFileList extends mixinBehaviors( [
       [this.Shortcut.RIGHT_PANE]: '_handleRightPane',
       [this.Shortcut.TOGGLE_INLINE_DIFF]: '_handleToggleInlineDiff',
       [this.Shortcut.TOGGLE_ALL_INLINE_DIFFS]: '_handleToggleAllInlineDiffs',
+      [this.Shortcut.TOGGLE_HIDE_ALL_COMMENT_THREADS]:
+        '_handleToggleHideAllCommentThreads',
       [this.Shortcut.CURSOR_NEXT_FILE]: '_handleCursorNext',
       [this.Shortcut.CURSOR_PREV_FILE]: '_handleCursorPrev',
       [this.Shortcut.NEXT_LINE]: '_handleCursorNext',
@@ -808,6 +810,15 @@ class GrFileList extends mixinBehaviors( [
     this._toggleInlineDiffs();
   }
 
+  _handleToggleHideAllCommentThreads(e) {
+    if (this.shouldSuppressKeyboardShortcut(e) || this.modifierPressed(e)) {
+      return;
+    }
+
+    e.preventDefault();
+    this.toggleClass('hideComments');
+  }
+
   _handleCursorNext(e) {
     if (this.shouldSuppressKeyboardShortcut(e) || this.modifierPressed(e)) {
       return;
diff --git a/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list_html.js b/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list_html.js
index 4ac4bb1416..df7cb00baf 100644
--- a/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list_html.js
+++ b/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list_html.js
@@ -310,6 +310,9 @@ export const htmlTemplate = html`
         display: none;
       }
     }
+    :host(.hideComments) {
+      --gr-comment-thread-display: none;
+    }
   </style>
   <div
     id="container"
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.js b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.js
index 5c77b0e0b1..19abdaf22e 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.js
@@ -298,6 +298,8 @@ class GrDiffView extends mixinBehaviors( [
       [this.Shortcut.EXPAND_ALL_DIFF_CONTEXT]: '_handleExpandAllDiffContext',
       [this.Shortcut.NEXT_UNREVIEWED_FILE]: '_handleNextUnreviewedFile',
       [this.Shortcut.TOGGLE_BLAME]: '_handleToggleBlame',
+      [this.Shortcut.TOGGLE_HIDE_ALL_COMMENT_THREADS]:
+          '_handleToggleHideAllCommentThreads',
 
       // Final two are actually handled by gr-comment-thread.
       [this.Shortcut.EXPAND_ALL_COMMENT_THREADS]: null,
@@ -740,6 +742,7 @@ class GrDiffView extends mixinBehaviors( [
     this._initCursor(this.params);
 
     this._changeNum = value.changeNum;
+    this.classList.remove('hideComments');
     this._path = value.path;
     this._patchRange = {
       patchNum: value.patchNum,
@@ -1277,6 +1280,12 @@ class GrDiffView extends mixinBehaviors( [
     this._toggleBlame();
   }
 
+  _handleToggleHideAllCommentThreads(e) {
+    if (this.shouldSuppressKeyboardShortcut(e) ||
+      this.modifierPressed(e)) { return; }
+    this.toggleClass('hideComments');
+  }
+
   _computeBlameLoaderClass(isImageDiff, path) {
     return !this.isMagicPath(path) && !isImageDiff ? 'show' : '';
   }
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view_html.js b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view_html.js
index e73515339b..3d30f77757 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view_html.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view_html.js
@@ -196,6 +196,9 @@ export const htmlTemplate = html`
         }
       }
     }
+    :host(.hideComments) {
+      --gr-comment-thread-display: none;
+    }
   </style>
   <gr-fixed-panel
     class$="[[_computeContainerClass(_editMode)]]"
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view_test.html b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view_test.html
index 98371dc5de..21d1144c72 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view_test.html
@@ -71,6 +71,7 @@ suite('gr-diff-view tests', () => {
     kb.bindShortcut(kb.Shortcut.TOGGLE_FILE_REVIEWED, 'r');
     kb.bindShortcut(kb.Shortcut.EXPAND_ALL_DIFF_CONTEXT, 'shift+x');
     kb.bindShortcut(kb.Shortcut.EXPAND_ALL_COMMENT_THREADS, 'e');
+    kb.bindShortcut(kb.Shortcut.TOGGLE_HIDE_ALL_COMMENT_THREADS, 'h');
     kb.bindShortcut(kb.Shortcut.COLLAPSE_ALL_COMMENT_THREADS, 'shift+e');
     kb.bindShortcut(kb.Shortcut.NEXT_UNREVIEWED_FILE, 'shift+m');
     kb.bindShortcut(kb.Shortcut.TOGGLE_BLAME, 'b');
diff --git a/polygerrit-ui/app/elements/gr-app-element.js b/polygerrit-ui/app/elements/gr-app-element.js
index 10ca963cde..ecb40a5c1a 100644
--- a/polygerrit-ui/app/elements/gr-app-element.js
+++ b/polygerrit-ui/app/elements/gr-app-element.js
@@ -350,6 +350,8 @@ class GrAppElement extends mixinBehaviors( [
         this.Shortcut.TOGGLE_INLINE_DIFF, 'i:keyup');
     this.bindShortcut(
         this.Shortcut.TOGGLE_BLAME, 'b');
+    this.bindShortcut(
+        this.Shortcut.TOGGLE_HIDE_ALL_COMMENT_THREADS, 'h');
 
     this.bindShortcut(
         this.Shortcut.OPEN_FIRST_FILE, ']');
diff --git a/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread_html.js b/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread_html.js
index 7c5c5c4c97..2bb5b66ea7 100644
--- a/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread_html.js
+++ b/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread_html.js
@@ -37,7 +37,7 @@ export const htmlTemplate = html`
     #container {
       background-color: var(--comment-background-color);
       color: var(--comment-text-color);
-      display: block;
+      display: var(--gr-comment-thread-display, block);
       margin: 0 var(--spacing-s) var(--spacing-s);
       white-space: normal;
       box-shadow: var(--elevation-level-2);