Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac Options) key, and then starting Firefox. Is the problem still there?

• 1 Download Firefox Full Installer For All languages And Systemsv40 {web link}
• 2 Uninstall Firefox from your computer {web link}
  DO NOT remove your profiles.
• 3 After, reboot the computer. Then run the full installer.

Some extensions are causing bookmark problems in Firefox 40, particularly "IE Tab" type extensions, "Tree Style Tab", and Tab Mix Plus (an update for TMP is pending).

I have this problem too. Is there another solution besides a complete reinstall? Will you all resolve this yourselves any time soon in the next release?

Hi WSC3, as a first step, could you test in Firefox's Safe Mode? That's a standard diagnostic tool to deactivate extensions and some advanced features of Firefox. More info: Diagnose Firefox issues using Troubleshoot Mode.

If Firefox is not running: Hold down the Shift key when starting Firefox.

If Firefox is running: You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" button > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

If the problem does not occur in Safe Mode:

Most likely the interference is coming from one of your extensions.

You can review, disable and often remove extensions on the Add-ons page. Either:

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

In the left column, click Extensions. Then check for IE Tab (any variant), Tree Style Tab, and Tab Mix Plus (you may need to update).

Thanks Jscher2000. I'll try that later when I have time. I know that you're just the messanger, but don't you think that this is why so many of us are reticent to update Firefox w/ every new release? I don't get any real value and I spend too much time fighting stuff like this. I use Sandboxie for security, so the security fixes are not really very compelling. (THanks for letting me vent.)

Hi WSC3, I don't really have an opinion on what people who don't post here are thinking. We do get complaints about broken add-ons, and add-ons that break Firefox's UI, after many updates. Usually these problems are detected and resolved during testing for popular add-ons, but with so many in use, and some dating back several years now, and no hope of their authors updating them, you can never have a problem-free update.

So FF works in safe mode. Can I go back to the previous version of FF where this issue didn't exist? (I have 40.0.0.3) I use the IETab a lot, as often pages (esp videos) won't work in FF.

Hi WSC3, what kind of videos don't work in Firefox? That sounds like a problem we might be able to solve if you still run Windows 7.

While it's not safe to go back to Firefox 39, there is an alternative if you can't live without IE Tab. That's the Extended Support Release version of Firefox (ESR). This is derived from Firefox 38 and while it will get security updates over the next several months, it will not get new features until next year. Maybe by then we can solve your video viewing problems, or you can get used to using https://addons.mozilla.org/firefox/ad.../open-in-ie/ to simply launch non-working sites in IE directly.

If you decide to switch, here is how I suggest installing it:

Clean Reinstall

We use this name, but it's not about removing your settings, it's about making sure the program files are clean (no inconsistent, corrupted, or alien code files). As described below, this process does not disturb your existing settings. Do NOT uninstall Firefox, that's not needed.

(A) Download a fresh installer for Firefox 38.2.1esr from https://www.mozilla.org/firefox/organizations/all/ to a convenient location. (Scroll down to your preferred language.)

(B) Exit out of Firefox (if applicable).

(C) Rename the program folder, either:

(64-bit Windows folder names)

C:\Program Files (x86)\Mozilla Firefox

to

C:\Program Files (x86)\Fx40

(32-bit Windows folder names)

C:\Program Files\Mozilla Firefox

to

C:\Program Files\Fx40

(D) Run the installer you downloaded in (A). It should automatically connect to your existing settings.

Note: Some plugins may exist only in that old folder. If something essential is missing, look in these folders:

• \Fx40\Plugins
• \Fx40\browser\plugins

My whole family has issues with videos and FF. We use W7 and W8. For example, on the PowerLine blog they'll post videos that won't play w/o going to IE Tab.

I'd still take the risks of v 39 for all this work troubleshooting.

Thanks for your help.

I removed the first IE extension IE Tab 4.0.201304...... Now bookmarks work.

For now. And I still have the IE tab option at the top, so I'm not sure what I lost in this change.

What does your suggested add-on do that my current one won't? I'm not sure I understand.

And thanks!!

WSC3 said

What does your suggested add-on do that my current one won't? I'm not sure I understand.

"Open in IE" allows you to launch a link or the current page in IE (outside of Firefox), or to store a site name so that happens automatically when you visit that site. Unlike IE Tab, it doesn't embed IE inside Firefox.