Yes, that would be a good practice.
No.
It should be on a single line. So DISCOURSE_SAML_CERT="MII...."
No.
Now for why the button is not appearing, which keys did you set in the app.yml except for the ones you mention in this post?
Yes, that would be a good practice.
No.
It should be on a single line. So DISCOURSE_SAML_CERT="MII...."
No.
Now for why the button is not appearing, which keys did you set in the app.yml except for the ones you mention in this post?