Try:

1. Right-click trash folder → "Repair Folder" → wait for sync to complete.
2. If "Empty Trash" option still missing: Right-click trash folder → Properties → General tab → Check "When getting new messages for this account, always check this folder" → OK.

Then try right-clicking trash again - the "Empty Trash" option should reappear.

Thanks for replying.

FYI, I'm using the German language version, so my translations of the menu items might not be correct.

Before trying your suggestions, I did what was described here: https://support.mozilla.org/en-US/kb/cannot-delete-messages

That didn't help, only new was the emails in the trash folder were shown grouped in older and today.

Your first suggestions didn't work either (I assume that was similar to deleting the folder from the profile). However, your second one did the trick. I checked that option and after a restart of thunderbird, the right click menu of the trash folder had the empty trash option again.

It's not obvious to me why this option is preventing the user from emptying the trash. If this isn't a bug, shouldn't this option be enabled by default?

Thanks again.

Unfortunately, I must take this back. Problem not solved. The trick helped just once.

Already the next day when new mail went to the trash, the right click menu item to empty the trash was gone again. I did mark the trash folder as read in hopes that this would help but it did nothing. Restarting Thunderbirds didn't help either. No way to empty the trash. I had the computer and Thunderbird running over night and this morning the trash was empty. So Thunderbird did this automatically somehow? However, the right click menu item to empty the trash is still missing.

I would like to be able to empty the trash when I see fit and I would like Thunderbird to reliably empty the trash every time the app is closed.

How can I fix this? How can I determine if there is something wrong with my setup or if this is a bug?

Thanks.

Thunderbird can be configured To empty trash at exit : it needs to be configured at the account level and for each account ( if you have more than one ) : go to Account Settings, then Server Setting and scroll down to the end and you'll see Message Storage and the option is "Empty trash on exit".

Suggestion : change your language to English only for testing purposes to see if that option would show up. If it shows up than this is a language issue / bug.

I've been using Thunderbird for many years, so I know very well that I can set the option to empty the trash on exit in the account settings. I've always had this option activated and as I've described already, this setting doesn't have any effect (not sure how long ago this started). I can close Thunderbird but when restarting it, the trash still holds all the mail from before.

I don't think that any localized Thunderbird version makes certain options disappear. A bug like that would have quickly been noticed and fixed, I assume. Like I mentioned I'm perfectly aware of this option, it has always existed in the English and German version, so that is not the issue at all.

Since the option (Empty trash on exit) clearly doesn't work I draw the conclusion that this is a bug. Same goes for the right click menu on the trash icon that doesn't show the option to empty it. I do have multiple accounts and the other ones do show the empty trash option as always. It's just this one account.

The problem persists. I'd like to be able to empty the trash when I see fit and I'd like Thunderbird to reliably empty the trash every time the app is closed.