A while ago I integrated my three main email addresses in the Android
Gmail app, and it works very well indeed. Spam-free bliss (after years
of struggling and wasting significant amounts of time trying to train
various spam filters) is a huge added bonus!
There is just one issue left to sort out: My two Gmail-based accounts
seem to be "smarter" than the "external" (GMX) account, in the sense
that once emails have been downloaded into Thunderbird on my PC or
laptop (all three accounts are set up as POP accounts), the Android app
no longer shows the new mail notification, whereas for the GMX account
the new mail notification remains active until I either dismiss it or
view the mails on the phone, if you see what I mean?
Is there something I can do in Thunderbird to rectify this behaviour for
the GMX account?