diff --git a/apps/web/src/components/AppSidebarLayout.tsx b/apps/web/src/components/AppSidebarLayout.tsx
index 918d28845068a..ecf9866356967 100644
--- a/apps/web/src/components/AppSidebarLayout.tsx
+++ b/apps/web/src/components/AppSidebarLayout.tsx
@@ -102,13 +102,20 @@ function SidebarControl() {
       ) {
         return;
       }
+      const richComposer =
+        event.target instanceof HTMLElement
+          ? event.target.closest('[data-composer-rich-text="true"]')
+          : null;
+      const selection = window.getSelection();
       if (
         isRichTextBoldShortcut(event) &&
-        event.target instanceof HTMLElement &&
-        event.target.closest('[data-composer-rich-text="true"]')
+        richComposer &&
+        selection?.isCollapsed === false &&
+        richComposer.contains(selection.anchorNode) &&
+        richComposer.contains(selection.focusNode)
       ) {
-        // The rich-text composer claims Mod+B for bold; the toggle stays
-        // available everywhere else, including the plain-text composer.
+        // The rich-text composer claims Mod+B to bold its selected text. Without a
+        // selection the toggle wins, since the composer holds focus most of the time.
         return;
       }
       if (
diff --git a/apps/web/src/keybindings.ts b/apps/web/src/keybindings.ts
index 24a4676050340..49f23b0f4a5ab 100644
--- a/apps/web/src/keybindings.ts
+++ b/apps/web/src/keybindings.ts
@@ -422,7 +422,7 @@ export function isOpenFavoriteEditorShortcut(
 /**
  * Whether the keypress is the rich-text bold chord (Mod+B without extra
  * modifiers). Tiptap binds the same chord, so app shortcuts captured ahead
- * of the editor must yield when the rich-text composer is focused.
+ * of the editor must yield when the rich-text composer has text selected.
  */
 export function isRichTextBoldShortcut(event: ShortcutEventLike): boolean {
   if (event.type !== undefined && event.type !== "keydown") {