The last redesign (the mail client, not the calendar) is what prompted me to finally abandon it. Each redesign in Mozilla products, be it Firefox or Thunderbird

The last redesign (the mail client, not the calendar) is what prompted me to finally abandon it. Each redesign in Mozilla products, be it Firefox or Thunderbird, seems to make them worse. At that point I don't know of a good GUI mail client for Linux[1]. I'm spending more and more time on Mac these days, where in the case of mail clients I'm using Mailmate and am very satisfied.