Impossible to use the latest Firefox with a newer profile

[elji]

I'm using both Firefox 67.0.4 and the Dev Edition 69.0b2 with 8 different profiles. I'm using each profile with either version of FF according to my needs, but I've just experienced something unexpected.

There's one profile I usually use on the Dev edition, and I've tried to open it on the regular Firefox, but I couldn't do it. It says I can't open this newer profile on an old release of Firefox (but I've got the latest release!). Only choice then is to exit the software or to create a new profile.

It certainly wasn't a big deal. I needed to close my tabs, waited for a download to complete, and it was fixed, but the ability to maintain different profiles, to use them at the same time, to share them between releases is a huge feature to me. I hope the devs will keep it.

[WaltS48]

Firefox uses dedicated profiles per installation since version 67.0.

Some users have multiple installations of Firefox, each in separate application folders. These separate Firefox installations previously shared a single profile by default. Beginning with Firefox version 67, Firefox will use a dedicated profile for each installation of Firefox (including Nightly, Beta, Developer Edition, and ESR installations) . This will make Firefox more stable when switching between installations on the same computer and will also allow you to run different Firefox installations at the same time.

REF: Dedicated profiles per Firefox installation

[elji]

Firefox uses dedicated profiles per installation since version 67.0.

Oh, yes. Thanks for quick reply. I've always had dedicated profiles (I have 8 profiles). The problem is with another profile which isn't the default profile for any Firefox installation.

[dickvl]

If you have a problem with accessing a profile then try to rename or remove compatibility.ini in this profile folder with Firefox closed.

[tanstaafl]

Or try using the --allow-downgrade command line argument.

[Brummelchen]

well, mixing up firefox and its profiles is no good

I'm using each profile with either version of FF according to my needs

stay with each firefox on its own profile - promised you will run into trouble sooner than later.

[WaltS48]

Firefox uses dedicated profiles per installation since version 67.0.

Oh, yes. Thanks for quick reply. I've always had dedicated profiles (I have 8 profiles). The problem is with another profile which isn't the default profile for any Firefox installation.

So you didn't read the article at the link I provided?

It is definitely possible to use the latest Firefox with a newer profile, just use the profile manager to create it.

It isn't possible to use the latest Firefox with a Beta or Nightly profile, unless like the article says you use --allow-downgrade when launching Firefox from the command line.

[elji]

Firefox uses dedicated profiles per installation since version 67.0.

Oh, yes. Thanks for quick reply. I've always had dedicated profiles (I have 8 profiles). The problem is with another profile which isn't the default profile for any Firefox installation.

So you didn't read the article at the link I provided?

It is definitely possible to use the latest Firefox with a newer profile, just use the profile manager to create it.

It isn't possible to use the latest Firefox with a Beta or Nightly profile, unless like the article says you use --allow-downgrade when launching Firefox from the command line.

Create a new profile is the last thing I want. I've got 8 profiles already, and they're all several years old...

But the -allow-downgrade is the trick I wanted.

well, mixing up firefox and its profiles is no good
stay with each firefox on its own profile - promised you will run into trouble sooner than later.

I need my 8 profiles. I understand a solution would be to have 8 different FF installations on the computer, but that would not be very practical...
The ability to choose different profiles is just great.
I've unchecked auto-updating on the Dev Edition, as I think this is the root of the problem. Everything was fine up to a few days ago. I guess there are too many differences between Firefox 67.0.4 and the Dev Edition 69.0b2.

[Brummelchen]

>> I guess there are too many differences between Firefox 67.0.4 and the Dev Edition 69.0b2.

maybe - i dont mix up profiles on different firefox builds, v67/68/69 have all its own.
and this is not by accident, i had my bad experience 35 builds ago and lost all my bookmarks du that. it took some time to find that out.

[elji]

You're right, one must be cautious. I have back-ups of all my profiles!