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Compatibility of TBird v78 and v91 using two different MacOS

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  • 1 has this problem
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  • Last reply by Matt

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Greetings,

I use TBird as IMAP on 2012 MacBook Pro.

For years I have been maxxed out at TB 78 under El Capitan. Now I have the opportunity to run TB 91 under Catalina (same computer, split internal drive).

Here are my questions:

Question part A: Can I just copy the entire current v78 profile into the Catalina partition and launch TB 91? Will everything look and act normal?

Question part B, after running TB 91 in Catalina, will it be possible to return to the El Capitan partition and check email using TB 78?

Thanks in advance

Greetings, I use TBird as IMAP on 2012 MacBook Pro. For years I have been maxxed out at TB 78 under El Capitan. Now I have the opportunity to run TB 91 under Catalina (same computer, split internal drive). Here are my questions: Question part A: Can I just copy the entire current v78 profile into the Catalina partition and launch TB 91? Will everything look and act normal? Question part B, after running TB 91 in Catalina, will it be possible to return to the El Capitan partition and check email using TB 78? Thanks in advance

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I would not suggest sharing or even trying to share profiles across Thunderbird versions. Prior to V68 the profile had been relatively stable, but since then with funds available to modernize some decades old and failing code the pace of change has accelerated. The storage formats used in the profile for data have been changing in significant ways with each major release.