After poking around at rclone’s repo and the web gui repo within it, I think this is a problem with rclone itself and how it sets up the web server for the gui. Changing the service to run with --rc-no-auth and remove the --rc-user and --rc-pass options removes the basic auth pop up, and shows the rclone web gui login which accepts the admin username and rclone password which was set during app install.
Perhaps this is a work around that could be changed in rclone-ynh? Since it still requires log in with the web ui it’s still secured, just not with that odd basic auth pop up. I could try to test making this change and submit a PR to the testing branch.
I’m still confused why jarod’s server doesn’t ask for it 