By default, Flutter web uses the browser's built-in context menu.

As of recently, it's possible to use a Flutter-rendered context menu like the other platforms.

void main() {
  runApp(const MyApp());
  BrowserContextMenu.disableContextMenu();
}

But there is a bug (#129692) that the Paste button is missing and never shows up.

The reason why it's missing is that Flutter first checks if there is any pasteable text on the clipboard before deciding to show the Paste button using the hasStrings platform channel method, but that was never implemented for web (original hasStrings PR).

So let's just implement hasStrings for web? No, because Chrome shows a permissions prompt when the clipboard is accessed, and there is no browser clipboard API to avoid it. The prompt will show immediately when the EditableText is built, not just when the Paste button is pressed.

This PR's solution

Instead, before implementing hasStrings for web, this PR disables the hasStrings check for web. The result is that users will always see a paste button, even in the (unlikely) case that they have nothing pasteable on the clipboard. However, they will not see a permissions dialog until they actually click the Paste button. Subsequent pastes don't show the permission dialog.

I think this will be the desired behavior for the vast majority of app developers. Those that want different behavior can use hasStrings themselves, which will be implemented in flutter/engine#43360.

References

Fixes #129692
Engine PR to be merged after this: flutter/engine#43360