Mozilla made some technical changes to what extensions like the Norton toolbar can do in Firefox 41, and Symantec has not yet completed its rework of the toolbar to make it compatible. They have an article about it here:

https://community.norton.com/en/blogs/product-update-announcements/firefox-41-and-norton-toolbar-compatibility

Naturally we disagree with their suggestion to roll back to an earlier Firefox due to publicly disclosed security flaws in Firefox 40. The ESR version is a better workaround.

The Extended Support Release (ESR) is designed for companies that require a longer cycle time between feature changes, and currently is based on Firefox 38. It will get security updates over the next several months, but not get new features, so changes in Firefox 41 related to add-on compatibility will not kick in for quite a while.

Norton is likely to continue to support ESR until the new toolbar updates are completed, maybe next month. After that, I'm not sure what they will do because normally they only support a small range of versions.

If you decide to try it, 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 38.3.0esr 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)\Fx41

(32-bit Windows folder names)

C:\Program Files\Mozilla Firefox

to

C:\Program Files\Fx41

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

Success?

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

• \Fx41\Plugins
• \Fx41\browser\plugins

This ESR seems like a more complicated installation and you seem to be suggesting the Norton Toolbar won't necessarily install normally with this version? "Note: Some plugins may exist only in that old folder. If something essential is missing, look in these folders:

   \Fx41\Plugins
   \Fx41\browser\plugins "

I think I will follow the advice of Norton though and just roll back to version 40 until the extension is updated, hopefully by months end.

It seems like it would be a good idea if maybe Mozilla made the consumer version more like the "ESR"

I don't like being forced to adapt to new changes so regularly by Mozilla this is getting out of hand. As it is I need extensions just to provide the "classic theme" I am not about to sacrifice my login agent, the browser will go first.

Thanks for your input but I am just looking for a straightforward download link to Firefox V40 Thanks again

Hi, first please see Norton Toolbar won't work with Firefox version 41.

If you still want to go back to an older version, which isn't recommended for security reasons, please see Install an older version of Firefox.

If your question is resolved by this or another answer, please take a minute to let us know. Thank you.

Hi Mychal, the "clean reinstall" procedure only takes a couple minutes and would be recommended for ANY rollback, whether to ESR or Firefox 40, as well as to resolve some issues when updates corrupt your program files.

As detailed above, the procedure DOES NOT affect extensions like the Norton toolbar (located in a Norton folder) or Classic Theme Restorer (located in your settings folder), and may only remove a very small number of plugins. You might not even have any of the plugins that install into those folders; the only one I can think of off the top of my head is the Windows Media Player plugin, and I don't see that on your list (Question Details > More System Details).

I realize this is new for you, but we help users do this multiple times a day on this forum, and as long as you do not delete your settings folder (the folder to rename is very clearly identified to avoid errors), it's seamless.

I should mention that there are some extensions that sometimes need to also be rolled back after a program version rollback. If an extension stops working, we can help you research that.