I never use the kind of antivirus program that controls access to the internet. Just Ad-Aware to recognize malware. No automated internet security, just my wits. No Windows firewall, just the hardware one in the router.

Some Firefox programs have problems when there is no firewall.

I followed the above link to http://xfinitytv.comcast.net/tv-listings?cmpid=xf_dash_tvl# and was able to trigger the freeze. I had Sysinternals Process Monitor running at the time, would the logfile be of use?

If it is not too long.

Here is the Process Monitor log (PML file) with non-firefox processed filtered out: https://www.dropbox.com/s/mcuur6za5e30ke2/FFLockup_Filtered.zip?dl=0

File received.

I can't read the file, so I've called the big guys to help you. Good luck.

Thanks to both of you.

FYI, all, this site, which I rarely visit, just froze the system for about 20 seconds: http://www.thecompanystore.com/

Nice dog, but no issues for me. I don't remember, have you tried to Start Firefox in Safe Mode {web Link} by holding down the <Shift (Mac Options) > key, and then starting Firefox. Is the problem still there?

Yes, I tried that a couple times. The results are in a couple of my posts on the first page. Thanks.

The problem seems to go away if I disable downloadable fonts. (about:config -> gfx.downloadable_fonts.enabled=False.

Hi charonn0, yes, if you have a ginormous font collection, it was reported in the past that the first page you visit during a session that uses a custom downloadable font -- more and more sites these days are doing that -- will lock up Firefox for a time while Firefox assimilates information about all the fonts on your system. Unfortunately, I'm not aware of any better workaround for this, other than never exiting out of Firefox, which really isn't that practical...

Earlier threads:

• Firefox causes desktop to freeze (Firefox 26)
• Firefox hangs on Websites (example: g2play.net) (Firefox 20.0.1)

One of the bugs referenced in the older thread was fixed in Firefox 31. Presumably you are running a version newer than that.

Using FF 36.0.4 on Win7x64 with 240 fonts installed.

Hi charonn0, 240 fonts is not so many. Your issue most likely is different than those old threads. Never mind!

I started getting this exact problem very recently, after downloading a long list of delayed windows updates, not sure if that has anything to do with it but it started happening like right after. Pretty much exactly as OP described, happens on high content websites like tumblr and deviantart, only once per boot though

Have any of the solutions posted worked for anyone?

Hi Wizzlbang, do you notice any association with use of Flash?

As a test, try setting Flash to Click-to-Play ("Ask to Activate"). This will delay Flash from starting on a page until you approve it.

To set "Ask to Activate", open the Add-ons page using either:

• Ctrl+Shift+a
• "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Plugins. Look for "Shockwave Flash" and change "Always Activate" to "Ask to Activate".

When you visit a site that wants to use the Flash, you should see a notification icon in the address bar and one of the following: a link in a black rectangle in the page or an infobar sliding down between the toolbar area and the page.

Feel free to ignore that if you aren't looking to play media on the site.

Also, try disabling the protected mode feature of the Flash player plugin. It has security benefits, but seems to have compatibility issues on some systems. There is a hidden setting for this:

(A) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

(B) In the search box above the list, type or paste flash and pause while the list is filtered

(C) Double-click the dom.ipc.plugins.flash.disable-protected-mode preference to switch its value from false to true.

This might not take effect until all Flash has been unloaded for a few minutes, or you close Firefox.

don't think it's flash related since flash doesn't activate on the deviantart front page