Right click the Back / Forward buttons to get a list of sites visited.

You can also install this add-on: https://addons.mozilla.org/en-US/firefox/addon/backforward-dropmarker/

Thanks for quick response :) Will try re-installing 4 later and try it out Still annoying to have to use two clicks instead of one.

Instructions for a clean installation then.

1. Go to Download Firefox 4.0.1 and download the installation file to your desktop.
   
   
2. Then go to Add/Remove Programs, scroll down to "Mozilla Firefox" and remove it, choosing to keep your bookmarks, customizations etc., (don't checkmark the box).
   
   
3. Then reboot and delete the folder called "Mozilla Firefox" at this location: C:\Program Files\Mozilla Firefox
   
   
4. Finally run the installation file you downloaded to the desktop earlier.
   

Your bookmarks, customizations etc., are maintained in a different location and will become available to you again once you complete the installation.

After you complete the installation, go to the Plugins Check page and update where necessary.

Did the "clean" reinstall as you suggest but unfortunately this does not help. The drop down list does not contain the page I want to return to.

I suspect that the problem may be that the page I want to return to is only available in cache. The server can't resend my page 2 with out re-filling out the details from page 1. So presumably in earlier versions of Firefox the back button would use the cache whereas Firefox 4 does not.

I can t find an option to control this behaviour. I guess I have to "downgrade" again.

Are you browsing in Private Browsing mode by any chance? Check via Firefox button | Options | Options | Privacy.

Change the setting at the top to "Use custom settings for history" and then the option for "Permanent private browsing" will appear.

If "Clear history when Firefox closes" is checkmarked, then sites you visited previously will also be deleted on exit.

Still no help :(

The url's are the same for my page 1 and page 2. Page 2 is a report from the server based on selections made in page 1. I believe this is referred to as POSTDATA.

In Firefox 3.6 the url appears twice in the drop down list but in 4.0 it is only there once.

BTW Do the developers see these posts?

Please do the following:

1. Go to Start, then Run, then copy/paste: firefox -safe-mode
   
   
2. In the next menu which appears, checkmark: "Reset toolbars and Controls".
   
   
3. Finally, click the button called "Make changes and restart".

If you haven't got "Run" on the Start menu, follow instructions here to enable it: http://blogs.msdn.com/b/tims/archive/2006/09/18/windows-vista-secret-3-bringing-back-start-run.aspx

Still no help :(

This has to be a change in the software. The response (my page 2) to submitting the filled-out form (my page 1) does not appear in the drop down list and so cannot be returned to.

I have to stick with Firefox 3.6.17 :(

Thanks for paying attention. I'll try again when a new update to v4 is available.

Try running Firefox in Diagnose Firefox issues using Troubleshoot Mode. If it functions properly in that configuration, then one of your add-ons is the culprit.