Alt+D scrolls down in LibreWolf

[LyndonGingerich]

In LibreWolf, when I press Alt+D to select the address bar, I instead scroll down as though I had pressed only D. This problem does not occur if I disable Vimium.

LibreWolf version: 136.0-2
Vimium version: 2.1.2

#75 is the only plausibly related issue I could find.

[philg-dev]

I just installed LibreWolf and did some basic testing, both with Vimium enabled and disabled.

It looks like LibreWolf for some reason neither triggers AltLeft key presses individually, nor does it provide the Alt modifier information on key combinations. So I think it's an upstream problem in LibreWolf itself.

I've found this issue on their codeberg repository, which might be at least related to the problem:
https://codeberg.org/librewolf/issues/issues/2165

In the issue they report shift and ctrl modifiers to be broken, with no specific mention of the alt modifier... For me shift and ctrl modifiers seem to be working without any issues. The issue was posted regarding MacOS and I'm on Arch Linux,... so maybe there's different flavors of that bug depending on the operating system.

You can use the nice debug page that @gdh1995 implemented at some point:
https://gdh1995.cn/vimium-c/keyboard-test.html

Maybe you can find another issue on Librewolf's repositories that suits your specific problem more precisely - or you can create your own bug report there.

If you find a more fitting issue or if you post one yourself, please comment the links here, so people can find it later on.

[LyndonGingerich]

All right, I have also opened an issue with LibreWolf.

[LyndonGingerich]

You can use the nice debug page

Whoa. Thanks to him!

I did some testing with this page. Alt+D is detected as D, without modifiers. Modifiers are detected for Ctrl+D and Shift+D (and Ctrl+Shift+D), but Alt is not detected in combination with the others.

Generally, it appears, simple character key inputs (such as Shift+D) raise three events: keydown, keypress, and keyup. Operational key combinations (such as Alt+D) raise only keydown. But Alt+Shift+D raises a keydown with the Shift modifier and a keyup without. I couldn't guess why.

[philg-dev]

@LyndonGingerich did you disable Vimium on the test page as is stated at the top of it?

If you didn't do that, Vimium will likely eat (consume) some of the events, if bindings exist for the things you're pressing. In that case it wouldn't be surprising to see such inconsistencies.

In any case: from my tests with Vimium disabled completely in Librewolf, the debug page never showed any alt modifier, when I pressed another key while I held down AltLeft.

e.g.: AltLeft + a doesn't have any effect by default, so it doesn't "disturb" the test by triggering any menus or browser actions - but still, no Alt modifier on Librewolf.