fix(chat): scope keyboard avoidance to Facebook IAB

src/app/chat/hooks/use-chat-keyboard-avoidance.ts

@@ -44,7 +44,7 @@ export function useChatKeyboardAvoidance({
   }, [active]);
 
   useEffect(() => {
-    if (typeof window === "undefined" || !PlatformDetector.isAndroid()) {
+    if (typeof window === "undefined" || !isKeyboardAvoidanceEnabled()) {
       return;
     }
 
@@ -72,16 +72,16 @@ export function useChatKeyboardAvoidance({
     const container = containerRef.current;
     if (typeof window === "undefined" || !container) return;
 
-    if (!active || !PlatformDetector.isAndroid()) {
+    const enabled = isKeyboardAvoidanceEnabled();
+    if (!active || !enabled) {
       clearBottomInset(container);
-      if (!active) baselineRef.current = readViewportBaseline();
+      if (!active && enabled) baselineRef.current = readViewportBaseline();
       return;
     }
 
     const baseline = baselineRef.current ?? readViewportBaseline();
     const visualViewport = window.visualViewport;
     const virtualKeyboard = getVirtualKeyboard();
-    const fallbackAllowed = BrowserDetector.isFacebookInAppBrowser();
     let frameId: number | null = null;
     let fallbackTimerId: number | null = null;
     let lastInset = -1;
@@ -194,8 +194,6 @@ export function useChatKeyboardAvoidance({
         applyBottomInset(resolution.bottomInset, resolution.source);
         return;
       }
-      if (!fallbackAllowed) return;
-
       fallbackApplied = true;
       applyBottomInset(
         resolveChatKeyboardFallbackInset(baseline.layoutHeight),
@@ -246,3 +244,9 @@ function getVirtualKeyboard(): VirtualKeyboardLike | null {
 function clearBottomInset(container: HTMLElement): void {
   container.style.removeProperty(CHAT_KEYBOARD_BOTTOM_INSET_VAR);
 }
+
+function isKeyboardAvoidanceEnabled(): boolean {
+  return (
+    PlatformDetector.isAndroid() && BrowserDetector.isFacebookInAppBrowser()
+  );
+}