Bug

When custom sign in is configured for an ArcGIS Online organization and the 'Display an option in your Sign In panel to allow members of other organizations to sign in using their ArcGIS Online credentials solely to access the organization content your members have shared with them' option is enabled, disabling it afterward does not remove the 'Not a member of this organization? Sign in to your account on ArcGIS Online' option from the organization's sign in page.