I have a question for any Mastodonian with DNS, email, and Thunderbird experience.

I don't have any definitive proof of this, but it _appears_ that when I send email using the Mozilla Thunderbird email client that email is more likely to be flagged as spam on the other end than if I use some other email client. Does anyone know if this is actually true, and if so, if anything can be done to stop that?

There are no other good Win/Linux cross platform email client solutions that I know of.