I do not think I have noticed any change. I have Firefox3.6 & 4RC installed.

The back arrow will be inactive in a new tab, until within that tab you have navigated to another page. If you click on a link within a page so that a new page opens in that tab the back button should then become active. Does that work for you ?

Of Course it doesn't - That's why I'm asking :) Here are 3 stages in images: 1. I choose new tab link 2. I click a link in the new opened tab 3. Back arrow is inactive  :-\

Sorry I was not doubting what you say, I only wondered if you were opening new tabs and expecting the back button to work immediately from a new tab.

The problem would appear to be on your own machine.
Presumably you already have a separate profile for each version of firefox installed.
You could try creating yet another new profile and see if you have problems in that. It may be worth trying ( obviously these change / loose settings )

• customize toolbars -> restore defaults
• safe mode [x] reset toolbars and controls

See also toolbar keeps resetting note the comments about localstore.rdf

Thank You John! You were close! McAfee SiteAdvisor 3.3 was the answer :D !!! And it's a pity because the extension was really useful. I had reinstalled all firefox with a bunch of plugins before found the buggy software.

I had site advisor installed last year but do not recall problems with it, although on searching the forum I note it has been reported preveously as causing problems with the back button eg https://support.mozilla.com/en-US/questions/784951#answer-144925

Does the forum allow you to mark posts solved with your own reply !? (I will comment on that elsewhere, it could be a usefull feature)

I only wonder why I didn't find this #answer-144925 before (though searched!) I hoped I was the first who found the right solution :(  ;)

I'm certain there would be some maniacs who would mark themselves "Solved" anywhere if they only could just to have more "solutions". But maybe marking whole discussion as "solved" (without marking the answer) would be a good idea.

It would presumably be easy to prevent counts of solved posts being added to the owners credit if the worry is that some would post merely to earn points. IIRC there are plans to revise the points system anyway (or am I thinking of some other board). But I suspect there are not many users that post large numbers questions, and any that do possibly do not find many solutions unaided.

I did comment

I have just thought, I can mark your post a helpful myself, I think, IF I sign out. NO that did not work, it gives me the option to mark my own posts as helpful, but not the owners posts as helpful.

I see you found the SOLUTION yourself, it was McAffee Site Advisor causing the problem

I also have this problem, and I don't have Site Advisor installed.

Hi RussWilliams,

It s quite possible that your problem is rather different from this one, so it may be of benefit to start a question yourself , including the system details etc that it prompts for. (use https://support.mozilla.com/en-US/questions/new )

There's a thread on McAfee's forum. They're supposedly working on it.

https://community.mcafee.com/thread/33973?start=0&tstart=0

Hi Gene1940,

You could start your own thread on this, there is a possibility the problem with the latest version of siteadvisor only occurs in certain circumstances, has anyone tested it in firefox safemode for instance ? and does the problem occur if the site advisor is used both with and without other McAfee software installed.

Thanks for a link, it could prove useful, however initially I saw no information in that to say specifically what McAfee themselves are working on other than :

"There are several issue which the SiteAdvisor team are aware of and are working on. {McAfee #17)"

I did notice a McAfee Mod mentioned making a post, but the Mozilla community is rather large and diverse and no link was included as to where the post may have been made.

On reading further I did note

"Refresh button, back button in FF4 and problems with the icon overlapping navigation buttons in IE9 in compact view have been reported. They [McAfee] are working on it. {McAfee#20]"

I think as a rule of thumb, if any addition such as 'site advisor' causes a problem with the basic default Firefox operations, it is that addition that is considered to be at fault, but sometimes problems may occur in only some circumstances or configurations.

Firefox is highly customisable, and has differing versions, there are many posts on the problem of 'site advisor' and firefox. The problem seems to predate (e.g.) the release of firefox 4. but I note it appears the problem occurs still with the latest version of site advisor / SiteAdvisor (3.3.129 ? )

I'm running FF3.6.3 and have not had this problem until yesterday. I do have site adviser but the problem seems to happen with Google. I haven't noticed it on yahoo search or MSN search. (I rarely use them) It doesn't exist in IE (which my wife uses) The problem seems to happen on the first navigation from the home page and to make the button work I have to click on the home page button. viola! it works.