I installed nextcloud-client through home-manager, but the entries are shown twice in Nautilus:
What can I do to fix this? According to this thread on the Nextcloud forums it’s because of the Implements=org.freedesktop.CloudProviders part in the desktop file, however I am unable to replicate that by copying the file to my home and launching the modified desktop file.
Launching the file probably will not help you but restarting Nautilus should. Make sure the Nautilus process exited, Nautilus will keep running for a bit until the last window closed.
Thought Nextcloud Client has already been updated to a version that was supposed to fix it. Make sure you update your system and you should not need the workaround.