(Edit 2 jan 2023: seems the plugin stopped working, won't show up how many unread mails you have anymore or show a preview of them.)

The plugin works, shows what emails you got with a preview of them. I give 4 stars because it ain't perfect:

-It shows only unread mail. If I select an email, a new tab opens to show it (perfect!). But if I delete that mail from that tab, the tab closes itself automatically (perfect!), but doesn't actually delete the email! It doesn't show up anymore in the plugin list of unread email, but if I open my email adress the mail is still there!

-Feedback page doesn't work (links to a search page, so I'm writing feedback here).