User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.99 Safari/537.36 Steps to reproduce: MAC 60.0b9 (64-bit) I installed the Beta on top of version 52. Actual results: Everything I have used seems to work but it asks to compact my folders. I had unchecked the compact option in my other installation but for some reason that setting was not imported to the new Beta version. Expected results: I would have expected all preferences to be imported from the previous install.

Which option? Tools > Options > Advances, Network & Disk Space: Compact all folders ... Note the the path to that option is different on Mac. This checkbox is driven by pref mail.prompt_purge_threshhold (note the misspelling) and that should survive and upgrade. Asking before an automatic compact/purge is driven by pref mail.purge.ask.

I actually do not know which setting. I know that I had found a setting to stop it asking to compact my folders. When I looked into it I found on the preferences "Advanced" page on the "Network & Disk Space" tab a checkbox "Compact all folders when it will save over" < Number > "MB in total That checkbox was unchecked on my original install but was checked on the Beta install. Unchecking that got the compact-folder request removed. I don't know/remember if that checkbox was manually unchecked or adjusted by something else I did in the original install.

weird

Your comment made me realise one more thing that could be affecting things. I upgraded to a newer macbook (2011 Air to 2018 Pro) about a month before installing the beta version. The import from my old computer took all night but seems to have worked flawlessly, could have given you some artefact in the settings tho. (It imported data, applications and settings but leaves out all passwords, but I guess that is a security feature.)

After reading the bug you referenced I can add that I do not ever compact my folders. I have always thought Thunderbird was asking to run some kind of compression on them. If Thunderbird actually asks about moving emails together and overwriting old deleted emails there might be a pedagogical problem in that request, maybe a link to some extended information could be good?

(In reply to Samuel Åslund from comment #5) > I have always thought Thunderbird was asking to run some kind of compression > on them. If Thunderbird actually asks about moving emails together and > overwriting old deleted emails there might be a pedagogical problem in that > request, maybe a link to some extended information could be good? You mean like this? COMPACT is the process of removing from the mail file/folder, emails which have been previously marked as deleted. It is not to be confused with compression, which is making a file smaller by some character encoding algorithm - https://en.wikipedia.org/wiki/Data_compression. See also https://support.mozilla.org/en-US/kb/compacting-folders

Yes, something like that. Especially the link to the Mozilla support page would have been useful. Your comment looked like something that already existed, so I actually had to look around at compacting in Thunderbird for Mac and was relieved to not find it neither on the preferences page or in the request dialog or by typing compact in the Help -> search util. Thanks for the info.