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Firefox menus vanish when the mouse moves onto them

Richard Ellwood
Richard Ellwood
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When I click on a Firefox menu (File, Edit, View, etc.) or the hamburger menu, or a drop-down menu on a web page, the menu appears. Then, when I move the mouse to hover over the menu, the menu vanishes. If, instead, I hold down the mouse button, I can move over the menu without it disappearing.

I'm using a focus-follows-mouse window manager (VTWM) and I think, somehow, Firefox is getting a focus change message when the mouse moves onto the menu. I think this because of the way the Firefox titlebar flickers from showing it's the active window to the inactive window, then active again, once the menu disappears.

Please advise.

Thanks, Richard

When I click on a Firefox menu (File, Edit, View, etc.) or the hamburger menu, or a drop-down menu on a web page, the menu appears. Then, when I move the mouse to hover over the menu, the menu vanishes. If, instead, I hold down the mouse button, I can move over the menu without it disappearing. I'm using a focus-follows-mouse window manager (VTWM) and I think, somehow, Firefox is getting a focus change message when the mouse moves onto the menu. I think this because of the way the Firefox titlebar flickers from showing it's the active window to the inactive window, then active again, once the menu disappears. Please advise. Thanks, Richard

Chosen solution

I found the solution.

Go to abount:config and set widget.gtk.grab-pointer to 1.

I hope that helps someone in the future.

Read this answer in context 👍 1

All Replies (3)

jonzn4SUSE
jonzn4SUSE
  • Top 10 Contributor
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Change Desktop and see if you have the same issues. X11 or Wayland? Do you have the same issue with Firefox in Safe Mode? https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode#w_how-to-start-firefox-in-4troubleshoot-modesf5safe-modesf

Richard Ellwood
Richard Ellwood Question owner
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I'm using X11 with the window manager VTWM, and no desktop environment. The issue doesn't occur on any full desktop system I've tried. I tried safe mode and that has no affect on the issue.

It seems that when a transient window is created, such as a drop-down menu, focus is switched to it when the mouse enters it, thus blurring the main Firefox window. Some UI code must have been recently added that tells Firefox to close any open transients when the main window loses focus.

Thanks!

Modified by Richard Ellwood

Richard Ellwood
Richard Ellwood Question owner
more options

Chosen Solution

I found the solution.

Go to abount:config and set widget.gtk.grab-pointer to 1.

I hope that helps someone in the future.