This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Downgrading from V89 to ESR (V78)

  • 1 reply
  • 1 has this problem
  • 18 views
  • Last reply by rsbrux

more options

Since I find the new Proton GUI a step backwards in usability, I plan to defer the inevitable as long as possible by moving to the ESR version (currently V78).

  1. How long are ESR versions supported?
  2. What is the ESR version release cycle?
  3. I plan to try using the -allow-downgrade command line option when downgrading, but the articles "Install an older version of Firefox" and "Command line options" are a bit short on step-by-step instruction. What is the correct procedure / sequence?
  4. I have serious misgivings that the result will be usable, given the large difference in version numbers. I have made a backup of my profile. Should I have problems with the downgraded profile, I will presumably have to create a new profile. How can I recover data from the backup profile and import it into the new profile?
  5. I am using Firefox Sync and hope that it will relieve me of some of the pain associated with a new profile. I am not syncing History however, because I prefer to keep the histories of my separate Firefox installations on different devices separate. Is there another way to preserve the history from a particular installation?
  6. If not, what can I expect from sequentially turning on history sync on my various Firefox installations?
  7. Will all history be merged or will subsequent history lists overwrite earlier ones?

Any further advice which might prevent me from screwing this up would be most welcome!

Since I find the new Proton GUI a step backwards in usability, I plan to defer the inevitable as long as possible by moving to the ESR version (currently V78). # How long are ESR versions supported? # What is the ESR version release cycle? # I plan to try using the -allow-downgrade command line option when downgrading, but the articles "[[Install an older version of Firefox]]" and "[[Command line options]]" are a bit short on step-by-step instruction. What is the correct procedure / sequence? # I have serious misgivings that the result will be usable, given the large difference in version numbers. I have made a backup of my profile. Should I have problems with the downgraded profile, I will presumably have to create a new profile. How can I recover data from the backup profile and import it into the new profile? # I am using Firefox Sync and hope that it will relieve me of some of the pain associated with a new profile. I am not syncing History however, because I prefer to keep the histories of my separate Firefox installations on different devices separate. Is there another way to preserve the history from a particular installation? # If not, what can I expect from sequentially turning on history sync on my various Firefox installations? # Will all history be merged or will subsequent history lists overwrite earlier ones? Any further advice which might prevent me from screwing this up would be most welcome!

All Replies (1)

more options

If I could have previewed the above before posting, I would have corrected the link to "Command line options" before posting. If I could have edited the post, I would have corrected it in the post after posting. Why are "Preview" and "Edit" only available for replies, and not for new posts?