3.6 can be found at http://www.firefox.com/all-older

What add-ons are they? There may be updates for the add-ons on the developers home page, or there may be alternative add-ons with similar functionality that work on Firefox 4.

it is also possible that some of the add-ons you are using have been abandoned and will never be updated.

To downgrade to Firefox 3.6.* you can uninstall Firefox 4, but do not select the option to "Remove my Firefox personal data". If you select that option it will delete your bookmarks, passwords and other user data.

You can then install Firefox 3.6.* available from http://www.mozilla.com/en-US/firefox/all-older.html - it will automatically use your current bookmarks, passwords etc.

To avoid possible problems with downgrading, I recommend going to your profile folder and deleting the following files if they exist - extensions.cache, extensions.rdf, extensions.ini, extensions.sqlite and localstore.rdf. Deleting these files will force Firefox to rebuild the list of installed extensions, checking their compatibility, and reset toolbar customizations.

For details of how to find your profile folder see https://support.mozilla.com/kb/Profiles

Thanks for your help, especially the directions about how to maintain my profile information.

The add-ons that I have found useful have been "image toolbar" and "cache viewer"

Previously I though Firefox made it easy to find the developers' home pages. Now I do not see any link, though I guess I could google them and try to find them that way.

There is an update to Image Toolbar, you can get it from https://addons.mozilla.org/en-us/firefox/addon/image-toolbar

The developer of CacheViewer has been working on a new version. They have created a veta version (0.7b) available from https://addons.mozilla.org/en-us/firefox/addon/cacheviewer/versions but that only lists it as compatible with a beta version of Firefox. No guarantees but it may work with Firefox 4. You cna first install the Add-on Compatibility Reporter extension which lets you install extensions that have not yet been marked as compatible with Firefox 4 to test to see if they work - https://addons.mozilla.org/firefox/addon/add-on-compatibility-reporter - after installing that you can install version 0.7b of CacheViewer to see if it works.

TonyE -- you are great!

I installed version 0.7b and so far it is working fine. And the updated Image Toolbar appeared after my initial post but also works fine with 4.0

Thanks!

You're welcome

"TonyE -- you are great!" - apart from my spelling in that post :)

Is a upgrade to the Extended Copy Menu plugin being planned? I am also going to downgrade to 3.6 until one is. I copy and paste stuff from pages all the time to search, make notes, drop addresses into google maps etc, and it is maddening not to have it. Why not just make copy as text part of standard Firefox?

You can try this this link which was posted in the Review page of this add-on:

https://addons.mozilla.org/ru/firefox/addon/extended-copy-menu-fix-vers/

Don't know much about this add-on, the link will link you to the Russian version of addons.mozilla.org. I guess it should work with your English Firefox too.