toeverything/AFFiNE · error

visualViewport is not supported

Error message

visualViewport is not supported

What it means

Warning logged by the mobile VirtualKeyboardProvider `onChange` when `visualViewport` is undefined — the environment does not expose the VisualViewport API needed to observe keyboard-driven viewport changes, so keyboard-change notifications cannot be delivered to subscribers.

Source

Thrown at packages/frontend/apps/mobile/src/app.tsx:106

        HEAVY: [30],
      }[style];
      const result = navigator.vibrate?.(pattern);
      if (!result) {
        console.warn('vibrate not supported, or user not interacted');
      }
      resolve();
    });
  },
  notification: () => Promise.reject('Not supported'),
  vibrate: () => Promise.reject('Not supported'),
  selectionStart: () => Promise.reject('Not supported'),
  selectionChanged: () => Promise.reject('Not supported'),
  selectionEnd: () => Promise.reject('Not supported'),
});
framework.impl(VirtualKeyboardProvider, {
  onChange: callback => {
    if (!visualViewport) {
      console.warn('visualViewport is not supported');
      return () => {};
    }

    const listener = () => {
      if (!visualViewport) return;
      const windowHeight = window.innerHeight;

      /**
       * ┌───────────────┐ - window top
       * │               │
       * │               │
       * │               │
       * │               │
       * │               │
       * └───────────────┘ - keyboard top        --
       * │               │                       │ keyboard height in layout viewport
       * └───────────────┘ - page(html) bottom   --
       * │               │                       │ visualViewport.offsetTop

View on GitHub (pinned to b4c8548c09)

Solutions

1. Feature-detect visualViewport before use.
2. Provide a non-viewport fallback layout.

When it happens

Trigger: Triggered on mobile when window.visualViewport is unavailable, so the virtual keyboard listener cannot be registered and a no-op unsubscribe is returned.

Common situations: Occurs in browsers lacking the VisualViewport API (older WebViews). Keyboard-aware layout adjustments will not work; upgrade the browser/WebView if needed.

AI-assisted analysis of toeverything/AFFiNE@b4c8548c09 (2026-08-18). Data as JSON: /api/errors/184d08cac9580e89. Report an issue: GitHub.