Open the fast/events/keydown-keypress-preventDefault.html test in WebView and type some character (e.g. 'a') in the text box that appears. The expected behavior is the test should log a message 'key down' below the text box and the text box should remain empty. In WebView, however, two message are logged, 'key down' and 'key press', and the text box displays the typed character.

The problem is, if a custom 'key down' event handler requests the caller to stop default event processing (by returning false), WebView does not properly suppress the subsequent 'key press' event.

It is unclear at the moment if there is an easy way to fix this problem. To implement the desired behavior, the Windows port, for example, has to jump through hoops and forcefully delete WM_CHAR messages from the Windows message queue whenever the key down event handler requests so.