Firefox since yesterday was checking for add-on compatibility on every browser start. It displayed the window that you only see after upgrading to a newer or downgrading to an older version of the browser. I first though that this was caused by the excellent sandboxing software Sandboxie, but this turned out to be not the case. I tested it by disabling Sandboxie before running the browser. The add-on update check was still displayed every time I started the browser.
I then checked if it was an issue with the prefs.js or another file that does not get updated properly forcing the browser to repeat the same process on every start.
While I was looking through the Firefox profile folder I noticed a user.js file in there. And that file, according to Mozilla does not exist by default. The Firefox developers furthermore note that that “once an entry for a preference setting exists in the user.js file, any change you make to that setting in the options and preference dialogs or via about:config will be lost when you restart your Mozilla application because the user.js entry will override it”.
This for my situation meant that the user.js file was blocking Firefox from updating properly. I have no idea how and why it was created in the first place, but decided to create a backup and delete it to see if it resolves the issue.
I closed Firefox first, copied user.js from the profile folder to the Windows desktop, and deleted the file afterwards. Firefox on next start did not check for add-on compatibilities anymore and the browser seems to have returned to its former self.
It is also interesting to note that the user.js file has not been created again by the browser.
Hope this helps Firefox users who are encountering the same issue that I did. I suggest you create backups of the file just in case for an option to restore it if this does not resolve the issue you are experiencing.
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this happens with me only in Nightly
As it’s suppose to.
I’m using Firefox UX, installed on December 24th and noticed that the Nightly hasn’t been updated since.
The developers must have taken a really long Holiday! :)
As far as I’ve always known, user.js is a user initiated file, it is neither part of the Firefox install neither created by Firefox during session, so the user.js you had in your profile must have been created by a user …
I use user.js to either change or confirm by rewriting any changes which could have been brought to Firefox without my consent, but this is delicate if for instance you have modified manually a setting in about:config or if you have authorized an add-on to modify what could be then again counter-modified by your user.js … one has to stay aware of the pros and cons of user.js, obviously !
I’m just wondering how I got it ;)
Perhaps someone gave it to you as a Christmas present! :)
Or maybe Martin is kind enough to consider his system as an example, rather than explaining that it could have been, but was not really, but you see the story needs an example …)
:)
I had a teacher like that, he wished so much to get understood that he’d put himself in the explanation. It means you really like getting things to be understood..
Martin is there a way to never have that update compatibility check?
I hate it and having all versions of Ffox installed I get that a lot.
Also in my profile folder I have Invalidprefs.js: is this supposed to be there and if those preferences are invalid how do I correct them?
Thanks
You can try this: http://www.ghacks.net/2011/11/01/how-to-turn-off-automatic-updates-for-individual-firefox-add-ons/
I had this happen to me occasionally at certain locations. I’ve always assumed that it was due to the local IT’s stupidity in implementation. Now I Know that it IS due to their implementation :)
Hi Martin,
I have the Tab app as an addon for my browser.
But yesterday onwards I cannot access it for some reason . When I checked the addon settings it was still active. What could be the reason???
Did Firefox update?
Sry for the delay.
Yea it updated , but it is not showing any message about being incompatible with this version or anything like that.
The user.js is not just user created but created by some software.
If the software is still on the system the user.js will be recreated
once again even if deleted with every new start of Firefox.
Perhaps the software that created it on your system has
since been removed since the user.js was not recreated.
Wonder what kind of software this was.
Ask.com is one apparently.
Others are claimed here too:
http://www.pchelpforum.com/fixed-hijackthis-logs/68199-ask-com-hijacked-my-firefox-help-2.html
I’m wondering as well what sort of software can create a user.js file, this is out of the protocol!. I’m not an expert (need I mention) but frankly I’ve never heard such a thing before. Anyway, if you already have a user.js, would that software overwrite yours with its own ?
Great tip, Martin. Good to know!
Thanks for sharing!
Sweet! Thanks a bunch I was having this problem for a bit and it would also keep blocking from entering sites saying they were not protected when their sites i visit all the time (Facebook, TD, CIBC)
Thanks Again :)
I got a problem like you, my firefox always check a compatibility for add on every time I started it… but I use your tips and my problem solved… thanks…..