Yes, in fact just today trying to use Dollar General's website to "clip a coupon". I scanned the QR code, found the coupon, tapped on it. I got a blank box (white box on gray background IIRC) in Firefox Focus, but a login screen on Vanadium.

And yesterday, same with a local club's website. Didn't even work in Firefox for Android, but worked in Vanadium. I got the website's custom loading sprinner, so that loaded and worked, but whatever was supposed to change the screen when everything else loaded, did not work.