Browser site not opening due to "auth."?

[flycaster]

This may be the wrong forum to ask this question. If so, please let me know where to post.
I have the Firefox app on my Android 13A-5G. When trying to enter one of my bookmarked sites, I am asked for my email address/password. These are being rejected, even though they are acceptable for this same bookmark site on my PC. I believe that the reason the address/pw isn't working on the android isthis because the android site's url is different than the PC's. Namely, when site opens, its url has an "auth." in its string. I've done some Googling on removing this auth, but the explanations were above my understanding. So, I'd appreciate knowing, in simple terms, if possible, how to remove the unwanted auth and just have this site open with a "regular" url so that my address/PW will work. Thanks.

 

[B. Diddy]

What happens if you toggle the "Request Desktop Site" option (if available -- that feature is in Chrome, but since I don't use Firefox, I can't be sure it's there as well)?