With commit (nextcloud/server@0d112d7#diff-8b87ec33b8bfb6e79af3a46d287408d2) the clientsecret was rewrite after reload (or backlink from oauth2) to "\_unmodified__"
To fix this behavior this commit saves client_secret temporary in localstorage
After reading from localstorage the client_secret would be deleted
Additionally:
If an user selects google drive and dropbox or onedrive: The plugins overwritten each other's events.
This commits fixes "invalid_client_secret".
The problem was:
Additionally: