I found it seems pretty easy to reproduce a similar timeout on TV-fis on try. When intermittent happens, test does receive focus event, but doesn't receive any mouse event.
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I found it seems pretty easy to reproduce a similar timeout on TV-fis on try. When intermittent happens, test does receive focus event, but doesn't receive any mouse event. https://treeherder.mozilla.org/jobs?repo=try&group_state=expanded&revision=11c21bb35b9cc25d52f014aa307f17d913469921&selectedTaskRun=EOful_i8RSu2p4KO0098iQ.0