Okay, now that we’ve established you are probably experiencing what I am describing..
Let me try to clear up a misunderstanding.
When you say “the same settings” you are talking in the language of Firefox “user profile preference overrides”
But Firefox allows and documents as a feature the concept of “systemwide prefernce overrides” that are merged with user supplied preference overrides" according to some precedent rules. User overrides are applied last after sytemwide overrides.
The Firefox sync feature doesn’t seem to work well when “systemwide preference overrides” are different across different systems.
Let me use my work system, which is a Fedora based respin as an example of what I’m talking about concerning systemwide overrides.
The fedora firefox package includes a systemwide preferences file
/usr/lib64/firefox/browser/defaults/preferences/firefox-redhat-default-prefs.js
When firefox starts up the overrides defined in the /usr/lib64/firefox/browser/defaults/preferences
directory get applied first.
But I also have system administrator preference overrides in /etc/firefox/defaults/pref
created by my employer that redefine the browser homepage to a work specific default, different from the fedora packaging default.
This directory of systemwide preference overrides under /etc/
gets applied after the stuff down in /usr/
because the firefox systemwide pref overrides in /etc/
represents local administrator intent, which should obviously override package vendor intent.
Then after that, my user prefence overriders which are stored in a profile specific directory under ~/.mozilla/firefox
are applied.
So on this system I see the firefox startup home page defined by a file down in /etc/
and not the application default, nor the fedora packaging defined override.
With me so far?
So when I fire up firefox with a fresh user on this system and check the about:config
in the browser what I see for browser.startup.homepage
is the start up page defined by the system administator from the overrides defined in /etc/
. I check my user prefs.js I see that there is no browser.startup.homepage
override defined in the scope of my user profile.
I can now set a user defined preference override using about:preferences
to Firefox homepage and choose “Firefox Home (default)” and I can confirm in about:config
that the value of browser.startup.homepage
has changed to about:home
. I check my user prefs.js I see that there is now browser.startup.homepage
override defined in the scope of my user profile.
From Firefox sync’s point of view there is no user profile override to sync until there is something listed in browser.startup.homepage
in the user profile’s preferences file.
Now on the same system if I install the firefox flatpak from flathub… which does not see the system administrator supplied systemwide pref override
s nor does it see the packaging systemwide it does not have a browser.startup.homepage
override defined.
If I try to sync these two firefox profiles using Firefox sync… one has browser.startup.browser defined and the other does not, which wins? If sync was working correctly shouldn’t all the profiles across all the systems now include the browser.startup.homepage
override with the about:home
defined? I’ve made an explicit user override request on one system, and sync should respect that and apply it to all synced systems right?
That’s not what is happening. Firefox Sync sees the value of about:home
as special and strips it from the user profile being synced, seeing it as redudant because it matches the application default.
This really appears to be bug in how Firefox sync works, its stripping out some user supplied overrides because sync doesn’t seem to realize that system overrides are allowed by the design of Firefox, and is making assumptions that user supplied overrides are redudant in some situations and strips them out.