Then you are in for a disappointment if you use Google as they have a mail paradigm that makes a single mail in IMAP something that does not exist. They create folders in their web interface on the fly basing everything on labels on an individual email in the All Mail database, but those emails become several emails once they are turned into IMAP which has no concept of labels and a central mail database and labels.

Note: As far as Google is concerned, unless you change setting on their web site. Once all labels are removed from an email is remains in all mail as an archive. That also means that the mail can not appear in the trash as that is just another label to Google.

Thunderbird defaults to moving deleted mail to the trash folder, when you empty the trash then Google will remove the trash label, and through use of web based setting Google can be convinced to remove mail after it is deleted and expunged from the trash.

I do not know of a way to have say the important label removed if you choose to use that inbox system Google has. Personally I just turned it off.

If you were to use a real IMAP implementation, not a "sort of" implementation as Google has you would do better, but that would require you to change mail providers to someone who has true IMAP, like GMX. The one offered by Micrisift is also not a true IMAP with other deficiencies other than those I discuss about Google.

Fundamentally email is a complex creature and how may expect it to work is far from the reality of what actually happens.

I'm not exactly eager to change my email, but it's beginning to look as if I need to get a different email provider so I can defend mys elf from all the cr*p that keeps showing up on my screen. Thank you.