Auto-fill on WiFi Captive Portal

Is there a way to auto-fill the username/password when connecting to a Wifi's Captive Portal? If possible, I would like a method that does not require root access. The portal opens with the system's default "HTML viewer" and not with Firefox/Chrome which would solve the problem since these browsers offer auto-fill. This question has been asked in the past and users suggested: - Captive Portal Controller app (but requires root) - CaptivePortalLogin app which claims to do this, but is in beta and does not seem to work for me. Version: Android 11 / MIUI 12.5