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Migrating normal Firefox profiles to Firefox ESR ones

  • 4 replies
  • 1 has this problem
  • 2 views
  • Last reply by cor-el

Michail Pappas
Michail Pappas
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We have around 1000 Firefox installations on our government organization, all installed via the Firefox MSI installer. Unfortunately, we came late to realize that the Firefox ESR would be a much more suitable product, compared to the normal Firefox branch.

Now, some years ago we would simply mass uninstall the normal Firefox and mass install the (latest) ESR version and all would be well. Problem is that we have to keep existing profiles (including passwords/bookmarks etc), something that is not supported in the latest Firefox builds.

Can anyone offer some advice/"hacks" to accomplish this? Note that whatever we'll do, we'll have to do it automatically, we lack the man-power to do this manually on a system by system basis...

Thanks in advance for any information provided.

We have around 1000 Firefox installations on our government organization, all installed via the Firefox MSI installer. Unfortunately, we came late to realize that the Firefox ESR would be a much more suitable product, compared to the normal Firefox branch. Now, some years ago we would simply mass uninstall the normal Firefox and mass install the (latest) ESR version and all would be well. Problem is that we have to keep existing profiles (including passwords/bookmarks etc), something that is not supported in the latest Firefox builds. Can anyone offer some advice/"hacks" to accomplish this? Note that whatever we'll do, we'll have to do it automatically, we lack the man-power to do this manually on a system by system basis... Thanks in advance for any information provided.

Chosen solution

What version of Firefox are you currently using and what ESR are you planning to move to?

There are environment variables you can set to allow the downgrade of Firefox without errors or you can launch Firefox with --allow-downgrade

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All Replies (4)

Mike Kaply
Mike Kaply
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Chosen Solution

What version of Firefox are you currently using and what ESR are you planning to move to?

There are environment variables you can set to allow the downgrade of Firefox without errors or you can launch Firefox with --allow-downgrade

Michail Pappas
Michail Pappas Question owner
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Currently we are at the latest "normal" Firefox, 93.0. As for the ESR version we're planning to move? Whatever is best for our case here (we could go either with the latest or one you specifically advise). I guess going with the latest (ESR 78 IIRC) would be the safest here.

Didn't know about the --allow-downgrade option. Is that needed only the first time one executes an older firefox version, or is it also needed in subsequent runs?

EDIT: Is there some policy option of Firefox enterprise that does the same thing, ie apply something like an --allow-downgrade?

Modified by Michail Pappas

Mike Kaply
Mike Kaply
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You'll want to go to 91 as 78 is end of life next month.

You only need to use allow-downgrade once when you move to 91 and from then on, it will launch fine.

Another possibility is to just delete the compatibilty.ini file from the users profile and you won't get the message at startup.

cor-el
cor-el
  • Moderator
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Note that you only need to delete compatibility.ini once to make it possible to generate a new compatibility.ini and set the version that last used the profile. Set the selector to Firefox 91.2.0 ESR: