I have the same problem Reinstalling Firefox and the xmarks addon does not help

It seems Xmarks version 3.7.8 is not OK or does not support FF 3.5. I get a strange popup with some HTML commands, which I can only close using the esc-key.

I think syncronizing wont't be possible until there is a bugfix or you reinstall an older version.

Using FF 3.5.9 (because some of my favorit addons are no further supported) on Vista Home

I think that it is a peculiar problem to OSX.

Same problem here with Windows 7. You'd think these guys would get things like this straightened out BEFORE they release a new version. This bug essentially shuts down FireFox if you use Xmarks.

It's the 4th of July but I think they had better get this fixed pronto.

Same problem, second time. This happened when I upgraded to Mac OSX 10.6.4. Yesterday July 4 upgraded Xmarks and Firefox crashed and did not open again. Had to resort to version 3.5. It will not work with 3.6.6. Also causing problems with Safari; not only it does not synchronize, it slows the browser and at times causes it to crash. I am using Chrome because of the problems caused by Xmarks. How do I get rid of it? This add on is pure CRAP! And how do I get to use Firefox 3.6.6 again, and without losing all my bookmarks?

Same here. Only solution for me was to create a new Firefox profile and delete the old profile.

+1 same

last Xmarks for firefox sucks

Mine gets stuck starting up too. It started happening last week. It happen on two of my laptops. It started happening after I updated to the latest version of XMarks.

I upgraded FF - and would not start with Xmarks plugin. Had to create a new profile without XMarks to make FF run.

Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en-GB; rv:1.9.2.8) Gecko/20100722 Firefox/3.6.8

Its a complete pain in the ar*e as I think the product is really useful! Not sure where the issue is - Xmarks or FF, but hope it gets resolved soon!

+1 same here.

This happens to me with any of the following enabled:

Greasemonkey, Xmarks, Lastpass

It crashes so quickly that the crash reporter does not even get invoked

@acdeag - Same here w/ regards to Greasemonkey. I've also got trouble w/ the 1Password browser integration. I can't find much about it either. Extremely frustrating.

This also happens to me with regards to greasemonkey. I downloaded greasemonkey and firefox prompted me to restart firefox, which I tried to do repeatedly but it just wouldn't work.

Like acdeag said, "It crashes so quickly that the crash reporter does not even get invoked" - this happens with me too!!

I tried deleting firefox altogether and the re-installing it, but the same thing happens. Now i'm stuck using shitty, inferior Safari instead!

Please help!!! I want to go back to using Firefox!!!

I have this problem running Gentoo Linux. I have found that if I start firefox from a terminal in safe mode and then shut it down, I can restart it once. Then I have to open it in safe mode agian, close it, then re-open it, etc.

Got the same problem under Linux i686.

SOLUTION: (Sep/12/2010)

Install Firefox Latest Beta which is compatible with xmarks:

http://www.mozilla.com/en-US/firefox/beta/

If you do that and when you try to install xmarks you notice it is not compatible with your beta but it is with a previous beta, uninstall your current beta, go back to the website and notice the download link and change the filename accordingly, e.g.:

http://www.mozilla.com/products/download.html?product=firefox-4.0b5&os=linux&lang=en-US

would be:

http://www.mozilla.com/products/download.html?product=firefox-4.0b4&os=linux&lang=en-US

If, as today, it's not compatible with b5 but it is with b4.

At least for me, the problem was solved.

Note that it can make many other add-ons not work anymore as they can become incompatible. I had to give up my theme and chatzilla, but worked.

This solution may soon be outdated.

icmp.request! Thank u SO MUCH!!! Problem solved! That was so simple, I just downloaded the Beta version and 'lo and behold, it actually worked!!! I'm a total n00b and actually have no idea what 'Beta' even means... i've heard the word, but know nothing about it.

Ahhh what a relief *sighs*! I thought I had lost my dear Firefox forever and was stuck using bloody Safari for ages. Not anymore! YIPPEEEEEEE!

Great start to my day, so thank you very much! :D

xxx

(Btw FYI 4 those wondering, I'm using Mac Snow Leopard version 10.6.4)