Not possible. Everything is being force updated and Volunteer Support has no say, only possible answers.

You are using a unsupported and insecure browser. Find a alternative to the addon.

52.5.0 ESR. It will continue to get security updates until May 2018, and you can download and install it from this page: https://www.mozilla.org/en-US/firefox/organizations/all/ Note : Legacy Extensions will be deleted or removed in any version update after May 2018.

You should make a backup of your Profile before going back and just because: https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

Please let us know if this solved your issue or if need further assistance.

First, Type about:preferences#advanced<enter> in the address bar. Under Advanced, Select Update.

[v56+] Type about:preferences#general<enter> in the address bar. Select Update.

Select Never Check For Updates.

Also turn off Use a background service to install updates

Install Older Version Of Firefox {web link} Be sure to read everything here.

If you still want to downgrade, look under; I still want to downgrade. Click the Directory of other versions and languages link. Look for the directory of the version that you want. But, remember that old versions may have security issues.

You should also check out Firefox; Extended Support Release {web link} ESR Notes System Requirements

Don't these extensions work in Firefox 52 ESR?

Firefox 52.5.2 ESR:

• https://www.mozilla.org/en-US/firefox/organizations/all/
• https://www.mozilla.org/en-US/firefox/52.5.2/releasenotes/