Firefox-esr from deb vs Firefox from snap (Kubuntu 26.04 LTS)

[DinoNerd]

I'm on kubuntu 26.04 LTS, upgraded from what I think was 25.10. The system came with firefox installed as a snap.

I had chronic problems with out of memory system hangs. I increased swap space beyond the default, installed OneTab, reduced firefox window and tab usage, etc. etc.

It all helped but I still had problems.

Recently I installed firefox-esr I believe I still have the latest and greatest; apt says I have 153.6.0esr~build

Unexpected result: the hangs are greatly reduced, or possibly completely gone. (It's only been a week, so I'm not sure which.)

I had been running firefox 1:1snap1-0ubuntu9.1 This is not the latest and greatest; I'd pinned it to reduce churn, possibly even before I upgraded to 26.04 LTS

I feel like this should be reported somewhere. Clearly either the non-esr version of firefox, or packaging it with snap causes what I experience as really bad performance problems. I suspect snap, but I haven't tested firefox (non-esr) installed as a deb, and don't really want to. (I'm happy to have a version that receives security updates and bug fixes without far too frequent user interface changes.)

Is there anywhere I can usefully post about this, where it might cause some investigation by e.g. distribution packagers? This looks like it could be a fixable bug.

Other useful info: I don't reboot the system unless its performance degrades, I need to install updates, or the power fails. I try to average less than 2 reboots a month.

[Edit to add: Also, I have a lot more firefox windows open than usual, since I'm not being encouraged to clean up by poor performance.]

[claydoh]

The firefox 1:1snap1-0ubuntu9.1 you see here is the version of the deb file that just is used to install the Snap version of firefox, the versioning here has nothing to do with the version of Firefox here, so it can be confusing. Pinning it will not have any effect on anything, since it doesn't actually do anything other than telling Snap to install FF.

Your FF snap IS going to be the most current version of the browser. If you look at the version seen in Discover or in FF's Help and Support section in its menus. Probably 159.0 or in the vicinity.

The ESR version is going to be actually older in a sense, but is a long-term support sort of version, so it is not the latest-and-greatest. But it works well for you, and is supported by Mozilla and gets security updates.


You could try installing a non-snap version of FF, but I suspect that your problems here will still be present, as they don't seem to be something that is specific to that package format.

[DinoNerd]

Of course the software version shown by

snap -list

would be obfuscated :-(

However, I used the instructions at the following URL to stop snap from force updating the firefox version.

https://snapcraft.io/blog/hold-your-...art%20about%20 the%20new%20functionality%20is%20that%20it%20still %20allows%20you%20to%20manually%20run%20snap%20ref reshes%2C%20for%20either%20the%20entire%20system%2 0or%20specific%20snaps

In particular, I used a shell command like

snap refresh --hold firefox

(I'm afraid I no longer recall the exact command, though it may be in my notes.) This worked. I was no longer bothered by messages demanding I update the snap, or have it updated for me bu the snap subsystem, and had no farther changes to firefox.

--

IIRC, there's some way to ask firefox its version, but it's not anywhere near as obvious as clicking on an "about firefox" entry in a menu.

OTOH, there is a command-line way to get the version, which I'd forgotten about while posting my message above.

$ firefox-esr --version
Mozilla Firefox 153.6.0esr

I no longer have whatever version of firefox snap had installed, so can't run it to check its version.

[claydoh]

well if you held FF at a version, maybe you have a buggy version?

$ snap list
Name Version Rev Tracking Publisher Notes
bare 1.0 5 latest/stable canonical✓ base
core24 20260824 2124 latest/stable canonical✓ base
firefox 159.0.1-1 9171 latest/stable/… mozilla✓ -


And for the deb version:

$ firefox --version

Mozilla Firefox 159.0.1


But again, the ESR version seems to suit you well, so no reason to switch at this point.

[DinoNerd]

well if you held FF at a version, maybe you have a buggy version?

That's certainly possible. I didn't record the sorts of things I would have done if I were a developer or QA person for any of the organizations involved. So there simply isn't the information to know for sure.