Opening popup windows is blocked by default in Safari and Firefox

In browsers (I tested Firefox and Safari), popup windows are blocked by default.

This means logging in with an OAuth provider won't work directly since the open a popup window. The browser will show a notification, but I'm afraid less tech savvy users will think the site is broken.

Maybe the blocking of a popup window can be detected and another option can be provided?

Or create a popup in the DOM and use an iframe to show the content of the OAuth provider.