955926 - With focus follows mouse, pop-up menus pop down when menu pops up on top of other app's window

Status: NEW

(Core :: XUL, defect)

Description

[Jonathan Kamens]

When I have GNOME configured with focus-follows-mouse, i.e., I select which window to focus on simply by moving the mouse over it, then any pop-up menu opened by Firefox or Thunderbird that is partially or completely on top of another app's window pops down immediately when I move the mouse into that region of the menu to try to select one of the items in it.

This, as you might imagine, is excessively annoying.

More information that may be relevant... GNOME actually has two different focus-follows-mouse modes, "mouse" and "sloppy". In the latter, moving the mouse from an app to the root window doesn't change focus, i.e., focus stays on the prior app even though the mouse is over the root window now. In contrast, in "mouse" focus mode, if you move your mouse out of window and over the root window, then the app loses focus and no app has focus.

This is relevant because when I use "sloppy" mode, I can work around this issue by closing the third-party window that's causing the problem, such that when the Mozilla app's menu pops up, there is no other app underneath it. Whereas when I use "mouse" mode, this problem occurs even when the pop-up menu is over the root window.

In other words, what seems to be happening is that the pop-up menus aren't maintaining focus on behalf of the app, and when the app loses focus the windows go away (as they should, I suppose). The problem, then is that pop-up menus need to be treated in such a way that they maintain focus on behalf of the app. I don't know if this is broken as a result of a change in Mozilla code or a change in the underlying windowing system, but I suspect Mozilla, because it doesn't happen with Emacs pop-up menus.

Another detail... if I pop up an initial menu that is partially on top of the mozilla app window and partially off of it, and move the mouse to the right of that menu, so that it's no longer over the main app window, the menu does NOT pop down. However, when I highlight a menu selection that has a sub-menu which pops up to the right, and then move the mouse into the sub-menu, that's when all of them pop down.

Comment 1

[Jonathan Kamens]

Anything I can do to get somebody to pay some attention to this bug?

If I regressed it to the nightly build in which it first started happening, would that help?