Make unread emails more obvious

[suzy]

Especially with the dark themes, I find the distinction between a read and an unopened message, by having the text as normal vs bold, not easy to see at a glance. The difference is visible, but it can be a subtle, and it would be nice to more easily get a sense of what's unread.

Maybe using different icons at the left, or a distinct colour for the subject text?

[salvadordf]

Added to the to-do list.

Thanks!