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Osdoba, Sascha

Apr 23, 2021, 2:32:07 AMApr 23
Dear all,

we are using "Firefox ESR 78.9.0" (78.10.0 will be rolled out this evening) and I have some customers
who are experiencing the above error message if they open firefox.

Mostly it wil appear on our citrix terminal server farm (Windows server 2012 R2 with Firefox x86 installed).

We create a new user profile (instead I saw that deleting "addonStartup.json.lz4" or start firefox in safe mode would
also help) but now I have an user who has seen this problem last week (I created a new user profil) and this week again,
today I did start in safe mode, refreshed firefox and after some clicking it starts fine again.

The old links with this error seems mostly from last year so maybe this error is still in ESR version?

We only install Firefox ESR via MSI, no langpacks, no extra things, just some GPOs.



Mike Kaply

Apr 23, 2021, 10:43:51 AMApr 23
to Osdoba, Sascha,
This error was specifically happening because of mismatched language packs. See:

I see no reason why this would happen on Windows.

When the user encounters the error, can you send me the addonStartup.json.lz4on the failing machine?

Mike Kaply

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Osdoba, Sascha

Apr 23, 2021, 2:47:55 PMApr 23
to Mike Kaply,

Hi Mike,


thanks for your reply, i will do next time we encounter this error – I haven’t done a backup today.





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