Cannot find a Thunderbird Spam file

I tried https://support.mozilla.org/en-US/questions/1567970

Here we go again with no real information at all to run with. Except one more crumb you are using yahoo. They have a bulk mail folder, not a spam folder. Why? Ask them! I have no idea why or how Yahoo continues to function, let alone the logic they use in naming they IMAP folders.

I do not use my backup Yahoo Mail boxes. I use Thunderbird as my go to mail app on xfinity. And need to get my emails that disappear in transit . is there a spam folder on Thunderbird ? If so, how do I find it!!

You can specify where to save spam at the 'spam settings' pane under 'account settings' for the account.

I do not use my backup Yahoo Mail boxes.

Yes you do. That is a fundamental issue that is causing some of the confuision. You are not aware of what services you use or what constraints that choice places on you.

I use Thunderbird as my go to mail app on xfinity. And need to get my emails that disappear in transit . is there a spam folder on Thunderbird ? If so, how do I find it!!

You need to understand clearly that IMAP mail is a syncronised service to the mail server. You see nothing in Thunderbird that is not on the server either folders or emails, so any idea you do not use your yahoo account is utter nonsense. A breeding ground for false assumptions and incorrect ideas.

Yahoo mail has not SPAM folder, they call is something else. In their web interface they call it a spam folder, in their IMAP interface they call the same thing a bulk or bulk mail folder. So Thunderbird for Yahoo has a spam folder called Bulk or Bulk Mail depending on how Yahoo are naming things this week. But Thunderbird has that folder by virtue of what the yahoo server has, not independently.

Thunderbird does do POP mail and this is entirely independent from the mail server and in those circumstances it has a junk folder (although there are moves afoot from some well meaning folks to rename that as SPAM but so far all they have done is make an awful mess of folder names.) However as Yahoo does not offer any mail they consider as spam to a POP mail client the junk/SPAM folder for that account is somewhat mute in this discussion.

In the folder pane in the left of Thunderbird, right click on the account and pick subscribe. See if there is a spam folder is in the list.

In the folder pane in the left of Thunderbird, right click on the account and pick subscribe. See if there is a spam folder is in the list.

Or a "Bulk" folder.