fix(webui): label temporary chat guidance

webui/src/components/thread/ThreadHeader.tsx

@@ -110,7 +110,10 @@ export function ThreadHeader({
                 align="end"
                 className="max-w-72 rounded-xl border border-border/70 bg-popover px-3 py-2 text-[12px]/[1.4] text-popover-foreground shadow-[0_8px_24px_rgba(15,23,42,0.13)] dark:border-white/10"
               >
-                {t("temporaryChat.description")}
+                <div className="font-medium">{t("temporaryChat.title")}</div>
+                <div className="mt-1 text-muted-foreground">
+                  {t("temporaryChat.description")}
+                </div>
               </TooltipContent>
             </Tooltip>
           </TooltipProvider>

webui/src/tests/app-layout.test.tsx

@@ -521,6 +521,13 @@ describe("App layout", () => {
     expect(heroTemporaryToggle.compareDocumentPosition(themeToggle)
       & Node.DOCUMENT_POSITION_FOLLOWING).toBeTruthy();
 
+    const user = userEvent.setup();
+    await user.hover(heroTemporaryToggle);
+    const temporaryTooltip = await screen.findByRole("tooltip");
+    expect(temporaryTooltip).toHaveTextContent("Temporary chat");
+    expect(temporaryTooltip).toHaveTextContent("Not saved to history or memory");
+    await user.unhover(heroTemporaryToggle);
+
     fireEvent.click(within(sidebar).getByText("Existing topic"));
     expect(window.location.hash).toBe("#/chat/websocket%3Aexisting-chat");
     expect(screen.queryByRole("button", { name: "Temporary chat" })).not.toBeInTheDocument();