It will leave your bookmarks etc. However it may well not solve your issue. Instead I suggest you try this First Lets make sure you have a working additional clean profile. Instead of a Refresh / Reset just create a new profile. Do NOT delete any of the original profile files or folders. Try Firefox in the new additional profile, does it work ok ? If so the next step is to fix that to be as close as possible to the original. (For instance you may have to sacrifice History to fix bookmarks issues.) # [[Use the Profile Manager to create and remove Firefox profiles]] #[[Recovering important data from an old profile]] # If necessary [[Can't add, change or save bookmarks - How to fix]] Second Install Firefox again BUT obtain the installer and then delete the original Firefox program files. We refer to that as a clean install and that will ensue you do not have any corrupted or additional program files. Follow these instructions: This process does not remove your [[Profiles - Where Firefox stores your bookmarks, passwords and other user data|Firefox profile]] data (such as bookmarks and passwords), since that information is stored in a different location. To do a clean reinstall of Firefox, please follow these steps: '''Note:''' You might want to print these steps or view them in another browser. #Download the latest Desktop version of Firefox from [https://www.mozilla.org mozilla.org] (or choose the download for your operating system and language from [https://www.mozilla.org/firefox/all/ this page]) and save the setup file to your computer. #After the download finishes, close all Firefox windows (or open the Firefox menu [[Image:New Fx Menu]] and click the close button [[Image:Close 29]]). #Delete the Firefox installation folder, which is located in one of these locations, by default: #*'''Windows:''' #**C:\Program Files\Mozilla Firefox #**C:\Program Files (x86)\Mozilla Firefox #*'''Mac:''' Delete Firefox from the Applications folder. #*'''Linux:''' If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it - see [[Installing Firefox on Linux]]. If you downloaded and installed the binary package from the [http://www.mozilla.org/firefox#desktop Firefox download page], simply remove the folder ''firefox'' in your home directory. #Now, go ahead and reinstall Firefox: ##Double-click the downloaded installation file and go through the steps of the installation wizard. ##Once the wizard is finished, choose to directly open Firefox after clicking the Finish button. More information about reinstalling Firefox can be found [[Troubleshoot and diagnose Firefox problems#w_5-reinstall-firefox|here]]. <b>WARNING:</b> Do not use a third party uninstaller as part of this process. Doing so could permanently delete your [[Profiles|Firefox profile]] data, including but not limited to, extensions, cache, cookies, bookmarks, personal settings and saved passwords. <u>These cannot be easily recovered unless they have been backed up to an external device!</u> See [[Back up and restore information in Firefox profiles]]. <!-- Starting in Firefox 31, the Firefox uninstaller no longer lets you remove user profile data.Ref: Bug 432017 and https://support.mozilla.org/kb/uninstall-firefox-from-your-computer/discuss/5279 [Fx31] Windows uninstaller will no longer offer the option to remove personal data --> Please report back to say if this helped you! Thank you.

Partial success, some questions left. I CAN save bookmarks in the new profile. 1. Since the problem is (or at least appears to be) in the profile, is there now no point in deleting and re-installing the Firefox program files? 2. I've read the Recovering data from an old profile article, but haven't tried it because I don't now have time to reinstall extensions and (maybe more time-consuming) replicate the option preferences. There SHOULD be an easier way!

1. Seldom fixes anything - so there is no point in doing it. 2. There is an easier way, but it involves planning ahead. When you set up a new Profile, backup that Profile before it becomes problematic. When it 'goes south' swap in the backup and then copy over the Firefox data files as described in the "Recovering data from an old profile" article.

You can check for problems with the <b>places.sqlite</b> database (bookmarks and history) in the Firefox profile folder. *https://addons.mozilla.org/firefox/addon/places-maintenance/ See also: *http://kb.mozillazine.org/Bookmarks_history_and_toolbar_buttons_not_working_-_Firefox *https://support.mozilla.org/kb/Bookmarks+not+saved#w_fix-the-bookmarks-file