Hello,
In the Release notes 5.1 document when you mention:
You mean that it should be enabled, right?
Regards,
Roberto
Ok I think I messed up! So it has to be disabled so that EasyMorph knows that it will expire, and needs to ask for another refresh token? What does this setting do exactly?
In any case, there is a typo with the “s” 
Hello @roberto ! This checkbox - Refresh token never expires - when ticked (default), indicates that refresh token would could be acquired only by manual re-authorization. That was the only option pre v5.0.
If you expect that your resource owner (OAuth server) can sometimes return new refresh token alongside with access token, you can untick this setting checkbox. But actually from our experience this is very rare scenario.
Really that should be something like 'unchecked' 