fix(app): keep web composer focused after submit (#4067)

The keyboard-sync change needed submission blur to dismiss the native keyboard, but applying it to every platform interrupted consecutive keyboard-driven messages on web and desktop. Keep submission blur native-only.

packages/app/e2e/browser/composer-focus.spec.ts

@@ -0,0 +1,29 @@
+import { test } from "../support/fixtures";
+import {
+  expectComposerDraft,
+  expectComposerFocused,
+  expectComposerVisible,
+  submitMessage,
+  typeIntoFocusedComposer,
+} from "../support/helpers/composer";
+import { openAgentRoute, seedMockAgentWorkspace } from "../support/helpers/mock-agent";
+
+test("submitting a message leaves the composer ready for the next message", async ({ page }) => {
+  const agent = await seedMockAgentWorkspace({
+    repoPrefix: "composer-focus-",
+    title: "Composer focus",
+  });
+
+  try {
+    await openAgentRoute(page, agent);
+    await expectComposerVisible(page);
+
+    await submitMessage(page, "First message");
+    await expectComposerFocused(page);
+
+    await typeIntoFocusedComposer(page, "Second message");
+    await expectComposerDraft(page, "Second message");
+  } finally {
+    await agent.cleanup();
+  }
+});

packages/app/e2e/support/helpers/composer.ts

@@ -38,6 +38,10 @@ export async function expectComposerEditable(page: Page): Promise<void> {
   await expect(composerInput(page)).toBeEditable({ timeout: 15_000 });
 }
 
+export async function expectComposerFocused(page: Page): Promise<void> {
+  await expect(composerInput(page)).toBeFocused();
+}
+
 export async function submitMessage(page: Page, text: string): Promise<void> {
   const input = composerInput(page);
   await expect(input).toBeEditable({ timeout: 30_000 });
@@ -49,6 +53,10 @@ export async function fillComposerDraft(page: Page, text: string): Promise<void>
   await composerInput(page).fill(text);
 }
 
+export async function typeIntoFocusedComposer(page: Page, text: string): Promise<void> {
+  await page.keyboard.type(text);
+}
+
 export async function sendDraftToQueue(page: Page): Promise<void> {
   await composerInput(page).press("Control+Enter");
 }

packages/app/src/panels/agent-panel.tsx

@@ -47,7 +47,7 @@ import {
   MAX_CONTENT_WIDTH,
   useIsCompactFormFactor,
 } from "@/constants/layout";
-import { isWeb } from "@/constants/platform";
+import { isNative, isWeb } from "@/constants/platform";
 import { useAgentAttentionClear } from "@/hooks/use-agent-attention-clear";
 import { useAgentInputDraft, type AgentInputDraft } from "@/composer/draft/input-draft";
 import {
@@ -1713,7 +1713,7 @@ function ActiveAgentComposer({
         serverId={serverId}
         workspaceId={workspaceId}
         externalKeyboardShift
-        blurOnSubmit
+        blurOnSubmit={isNative}
         isPaneFocused={isPaneFocused}
         value={agentInputDraft.text}
         onChangeText={agentInputDraft.editText}