Once you add a new account, you have to race to open up the settings and turn off the "Download all mails" setting that is hardwired as the default. Even after having done that, I am left with GB of copies of mail messages that I don't want to store on my local system. How do I get rid of those local copies? Compacting doesn't seem to do it - there's no "Compact now" button in any case. I don't know what "when it will save over N MB in total" means, exactly. Save compared to what? Now 50% off! Likewise, if I have Message Synchronizing (Keep messages in all folders etc) turned off, but Disk Space - Synchronize all messages locally regardless of age is still selected, is it going to download copies anyway or no? If it will download anyway, or if it already did download, if I change the Synchronizing setting to "only the last 30 days" will it remove the older local copies? When? The only "recover disk space" option deletes both local copies and originals on the remote server. There really should be a "purge local copies" action available in the client. It may be that it is OK to go out to the OS and remove certain files myself, but maybe it won't be in the future. Every note that is about "Simply open a Terminal window..." describes specific files that don't quite match what I see here in May of 2024 on a Mac. But the tool itself knows what can be removed safely.