Hi, Masayuki! Thank you for reporting this bug! I wonder if you had scrolling of the toolbar disabled? I can't reproduce the bug with a scrollable toolbar.
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Hi, Masayuki! Thank you for reporting this bug! I wonder if you had scrolling of the toolbar disabled? I can't reproduce the bug with a scrollable toolbar. possible duplicate of [1907638](https://bugzilla.mozilla.org/show_bug.cgi?id=1907638)