The update process is based on: https://update.freshrss.org/ this website doesn't respond something special: "NO_VERSION_SPECIFIED"!
Is there any problem, something wrong? Is this website who drives upgrading process?
This website isn't intended to be used via a browser. It is only used by FreshRSS itself when you go to Settings -> Update.
But it doesn't work from Settings→Update so…
Try by yourself: https://update.freshrss.org/?v=1.6.3 it returns: "NO_UPDATE 1.6.3" but there is a 1.7.0 released so we can't upgrade? The FreshRSS feed, added on installation process, indicates the release of 1.7.0 version…
Will be improved as part of https://github.com/FreshRSS/FreshRSS/issues/907