I haven't looked into this more closely, but the first thought that comes to mind as a developer is, maybe the page content that Firefox shows you after an update (you know, the kind of "What's new with this browser?" stuff that browsers tend to show after being updated) is interfering with the pages it is supposed to open on that same run based on command line parameters. Again, I haven't looked into this, it's just a hunch.Jakob77 wrote: Tue Apr 08, 2025 4:54 am If you want to replicate the error you may have to run the Terminal command as the very first thing after updating.
If that is the case, it could potentially be mitigated by disabling all that stuff that causes out-of-the-ordinary pages to show on the first run after an update. If there is no actual fix forthcoming, that is.
So at the very least all relevant settings starting with "startup.homepage_override" would need to be switched to disable such overrides. See the browser's about:config and turn off at least browser.startup.homepage_override.mstone and startup.homepage_override_url and see if it makes a difference in the long run. There are potentially more settings related to the page opening behavior after an update.