I neglected to add that apparently one can bounce e-mails with MailBird and the MailWash tool.

I don't know about a filter action that bounces unwanted mail, but a filter like the one in the attached picture will move messages from those not in your address books to another folder, or similar action. There is also a Quick Filter Bar button to show mail only from those contacts in your address book.

I see that one can filter messages from unwanted senders using Thunderbird.

You certainly can.

I'd like to see the feature whereby e-mails from unwanted senders actually bounce as if my e-mail address were not valid.

Interesting if somewhat useless idea. Can you set a snail mail filter to have mail delivered that you do not want to be bounced by the post office, or even by your letter box when someone tries to poke the mail through the slot?

unlike snail mail your mail is accepted by your mail provider on your behalf. When the sending server tries to deliver mail to your provider on your behalf your provider checks that the email address exists on their service. If it does exist it accepts the mail for delivery. If it does not exist it refuses accept the message for delivery (bounces) the message. The problem with these assorted products that send belated bounce messages about mail accounts post the delivery of the message to the server is that 6they are clearly a lie if anyone bothers to check the rejection times against the initial delivery.

Then there is the issue of who cares if the message bounces. Apparently you do, or would like to. However no spammer is going to be interested. They expect significant delivery issues in their mailings and as it costs them essentially nothing to send emails, they are not in the business of culling dead email address from their lists. Least of all addresses that are supposedly dead minutes of hours after the mail server accepted mail to that address for delivery.

Then we have the third group. Those that offer access to web sites in exchange for you accepting delivery of marketing emails. Sure they will check that the mail they are sending is not bouncing. if it is, they will block your access the the relevant web sites that accepting mails is a condition of access. Rather inconvenient you you, nothing to those cancelling your membership based on a terms of service violation.

I think that having a set filter that merely deletes the unwanted sender's message is not adequate albeit somewhat useful.

In my use case it is perfect. I decide what I want to see and see only that. The sender is not in the loop.

Also, I would like to have the ability to set up things so that only people who are in my address books can send me messages.

That is quite simple using a filter. You just filter the to to be in a particular address book. Just be careful how you set it up however as when your bank sends your bank statement you will not get it unless the address is already in your address book. The same sort of caveat goes for most true commercial operations. Things I get by email like my payslip come from an address I do not have in my address book, it is my employers accounting provider. I did not even know they were associated with the provider until after I got my payslip.

Can anyone oblige and do an add-on or build these features into a Thunderbird update?

Personally I see Thunderbird already delivering the filtering capability you require. The bounce message services offered by mail servers are really outside the scope of a mail client that gets mail long after it is actually delivered to the mail server.

However if you feel that you have a legitimate suggestion there is a feedback forum here for you to make such suggestions.

Yes, correct, and there is a fourth non-generic group of senders who have one's address but who refuse to cease sending personal messages even after they have been admonished not to do so. I would prefer to have their spurious and clingy, weirdo e-mails bounce back to them, and not merely blocked and shunted to the trash.

Yes, correct, and there is a fourth non-generic group of senders who have one's address but who refuse to cease sending personal messages even after they have been admonished not to do so.

If you feel that strongly, I suggest you undertake some real world litigation to have a restraining order imposed on them to cease communication.