Scrolling page with arrow keys no longer works

[Flack]

I have updated Kubuntu to 24.04 yesterday and since then, I can't scroll webpages with Arrow up/down anymore. Normally, pressing those keys would just move the page up and down, now the arrow keys for some reason behave like the tab key, i.e. the jump from one link (or clickable element) to the next.

I also have a strange mouse issue since the update: When I scroll down a page, occasionally it automatically scrolls back up. But I'm not 100% sure that is specific to Firefox, it may have happened in an electron app, too. I just thought I'd mention it here because I currently have no reliable way of scrolling a page in Firefox (scrolling with the spacebar works, but it's not so user friendly, since it scrolls very far each time)

[Flack (ccbflack)]

Update: I'm not sure how this could be related, but I just rebooted and disabled SecureBoot, and now the behavior is back to normal

[Amin Bandali (bandali)]

Indeed I'm not sure how that could be related, since to my knowledge SecureBoot is supposed to only affect the boot process and not anything beyond that.

Was the disabling of SecureBoot the *only* change you made across those reboots? Would you be able to try undoing that change and reboot, and see if the issue indeed reappears?

[Flack (ccbflack)]

yes, SecureBoot was the only change I made. I had already tried rebooting a couple of times before changing SecureBoot, so the reboot itself can't have solved it.

I have now turned SecureBoot back on, and so far the problem did not come back. It almost seems like the update somehow confused the keyboard/mouse driver and changing something triggered a re-detection of the correct devices. Or something. In any case, it looks like I can't reproduce any longer.

[Amin Bandali (bandali)]

Hmm I see, thanks for the details. I'm not sure, but you may indeed be right about enabling Secure Boot causing complications with device drivers / kernel modules.

Are you by any chance using the official Canonical-provided kernel on your Ubuntu installation, or are you perhaps using a third-party/unofficial kernel? I was looking at https://wiki.ubuntu.com/UEFI/SecureBoot and noticed this sentence:

> In the case of unofficial kernels, or kernels built by users, additional steps need to be taken if users wish to load such kernels while retaining the full capabilities of UEFI Secure Boot.

And this:

> Unsigned modules are simply refused by the kernel. Any attempt to insert them with insmod or modprobe will fail with an error message.

Which made wonder if you may be running into this with a custom/unofficial kernel.

[Amin Bandali (bandali)]

Also since you mentioned you can no longer reproduce this and it doesn't seem firefox-specific, I'll close this but please feel free to reopen or report a new bug (perhaps against the kernel) if you run into the issue again.

[Flack (ccbflack)]

well, I didn't self-compile or add some PPA, so it should be the default kernel, but from Kubuntu, if that makes a difference. uname -r shows

6.8.0-31-generic

in case that helps. But yeah, I guess I'll reopen against the kernel if the problem ever pops up again