For a start I want to say that make sure Thunderbird does not become a bloatware, software often tends to do! I just like it as it is, neat and manageable.
Next, back in the days before I started using Thunderbird I had IncrediMail as my mail client. It has a grand function that I have missed ever since. The ability of “bouncing an email to sender”.
You receive a lot of junk mail yourself, right … but you will direct a new one into the Junk folder. But even the same junk still will keep coming it will automatically end up in the junk folder due to your prior selection status.
Say you do not want a sender to know that your mail address still is valid, like an former lover … that's where the beauty of bouncing comes in. The marked email/sender for bouncing received a fake email with a inauthentic sender reference stating that the email did not arrive at the intended email address and that the email address was not found. The target for the bouncing would therefore assume that the email address was obsolete and most likely never write you again! Just loved that function 🙂
Cheers Bjarne