When in read-only mode, changing settings fails silently without an error message. tpokorra encountered this issue while trying to modify the “allow restore” setting in the backups section and initially suspected a problem with their nginx reverse proxy. They suggest displaying a more specific error message to indicate that changing settings or logging out is not available due to read-only mode. codinghorror points out that a giant banner is displayed at the top of every page when read-only mode is enabled, but tpokorra notes that the connection between “interactions” and administrative tasks may not be immediately clear, especially for those who are not familiar with the system.
I tried to set in the settings, Backups, allow restore. But it did not allow to save it.
Because there is no error message, I first thought something was wrong with my nginx reverse proxy, showing 405 (Method Not Allowed) errors.
It took a while until I realised that I had set the read-only mode, and that was the reason why all POST and DELETE (user logout) requests failed.
It would be good if there was an error message showing that currently changing the settings or logging out is not available due to read-only mode.