@Gargron
Until now, i didn't thought about using a #RSS feed reader to follow #Mastodon accounts.

But i use #Flym. Also used #Feeder. Following RSS feeds outside Mastodon.

Flym (Leichter und moderner Feed-Reader)
https://f-droid.org/packages/net.frju.flym/

Feeder (Ein großartiger, kostenloser und quelloffener RSS-Feedreader)
https://f-droid.org/packages/com.nononsenseapps.feeder/