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The Firefox pop-up context menu has a 4px transparent border around it:
The red border around it is made with userChrome, and ideally there shouldn't be any gap
$ cat userChrome.css
menupopup {
border: 10px solid #ff0000 !important;
}
Firefox version:
$ firefox -version
Mozilla Firefox 128.0
It is annoying because Picom makes the window background blurred and brings border shadow that is drawn farther around window.
The screenshot was taken when the Picom was shut off, so there is no conflict with it.
I've found a github issue https://github.com/black7375/Firefox-UI-Fix/issues/303 which says that XDG_CURRENT_DESKTOP var must be set, but I have a plain BSPWM and no idea what should go in it.
I tried setting it to GNOME but it didn't change anything.
There is a pretty straightforward workaround for it - excluding popup and menu windows from shadowed and blurred categories in the Picom configuration - but the pop-ups look inconsistent and out-of-place.
I wonder if there is any solutions that don't require me to disable shadow and blur.
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