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Downgrade from Release 148.0.1 to 140.8.1esr

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  • Last reply by Rick
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k_s
k_s

Hello,

for some reasons I need to downgrade a TB installation (Mac silicon 148.0.1) to the ESR channel, 140.8.1esr for Mac silicon.

I read articles in the KB where Mozilla discourages this, but I would avoid to move 15Gb circa of emails by hand copying and pasting them...

So is there anyone that has tried this before? Any suggestion how to do it without loosing e-mail in th process?

Thanks fr your support.

Hello, for some reasons I need to downgrade a TB installation (Mac silicon 148.0.1) to the ESR channel, 140.8.1esr for Mac silicon. I read articles in the KB where Mozilla discourages this, but I would avoid to move 15Gb circa of emails by hand copying and pasting them... So is there anyone that has tried this before? Any suggestion how to do it without loosing e-mail in th process? Thanks fr your support.

All Replies (2)

david
david
  • Top 10 Contributor

Just to be sure I am giving reasonable advice, I took a 148 version on a Windows PC, and installed a 140 version over it. The only problem I encountered was the need to delete the compatibility.ini file in the profile prior to thunderbird starting, and then to reenter passwords after starting thunderbird. Although my testing was minimal, all seemed to be working. I don't know Macs, but I hope this info is helpful.

Rick
Rick
  • Top 25 Contributor

Before you downgrade, if you tell us what problem you are trying to solve, we may be able to save you some time and effort. Why do you want to downgrade? Why do you think that you might have to "move 15Gb circa of emails by hand copying and pasting them"?

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