diff --git a/desktop/src/features/messages/ui/MessageComposerToolbar.tsx b/desktop/src/features/messages/ui/MessageComposerToolbar.tsx
index 6d03805c6..f7efac52c 100644
--- a/desktop/src/features/messages/ui/MessageComposerToolbar.tsx
+++ b/desktop/src/features/messages/ui/MessageComposerToolbar.tsx
@@ -322,13 +322,16 @@ export const MessageComposerToolbar = React.memo(
           {onStopAgent && !isSending ? (
             <Button
               aria-label="Stop agent"
-              className="rounded-full"
+              // Icon size set here so it wins the base [&_svg]:size-4 via
+              // class merge — sizing the svg directly leaves both rules
+              // competing and the glyph off-center.
+              className="rounded-full [&_svg]:size-3.5"
               data-testid="stop-agent"
               onClick={onStopAgent}
               size="icon"
               type="button"
             >
-              <Square aria-hidden className="h-3.5 w-3.5 fill-current" />
+              <Square aria-hidden className="fill-current" />
             </Button>
           ) : (
             <Button
diff --git a/desktop/src/shared/styles/globals/animations.css b/desktop/src/shared/styles/globals/animations.css
index db61cf356..1befca1fd 100644
--- a/desktop/src/shared/styles/globals/animations.css
+++ b/desktop/src/shared/styles/globals/animations.css
@@ -165,6 +165,13 @@
 .buzz-shimmer::before,
 .shimmer::before {
   animation: buzz-shimmer var(--buzz-shimmer-duration) linear infinite;
+  /* Truncate exactly like the base text: the overlay repeats the FULL
+     data-shimmer-text, and without its own ellipsis it paints the clipped
+     characters right over the base ellipsis on truncating labels (sidebar
+     titles). Same font + box → the ellipsis lands in the same spot. */
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
   background-clip: text;
   background-image: linear-gradient(
     90deg,