bredge: "modern"? that's something that should be more clearly specified for something like this

bredge: SeaMonkey has support for themes, that can change the UI at least to some extent, so it may be possible to get some of the appearance you're looking for. But if you're looking mainly for "like thunderbird", any chance using thunderbird would be easier? Or are you interested in something Thunderbird does not offer? (Say, being part of a suite, or supporting extensions?)

bredge: I'm not saying you can't get what you want, just trying to better understand your question.

I would like to trash every single incoming email with emojis in the subject

...sadly even legit places (including BANKS!) started using those

still, 99% of the mail with emojis is spam

how I would achieve such a rule on Mail&News while excluding known senders?