Can't login to sites that use microsoft azure for authentication

[Fringetastic]

I wrote up this issue on the mozilla forums. Copying it here:

I can no longer sign in to sites that seem to use microsoft azure for authentication. Including:
www.comed.com
people's gas through https://www.peoplesgasdelivery.com/
www.athletico.com which goes to https://myathleticob2cprd.b2clogin.com/

All of them return a page that just says "Bad Request" after I enter my credentials and proceed.

Resolution:
I found it is an addon causing the issue: FoxyTab. I disabled all addons, re-enabled them one by one and then in combinations, and used ctrl-F5 to reload the pages. FoxyTab is the one common addon. When disabled, the login process continues on each of the sites I listed.
<<<

[erosman]

Have you enabled Clean URL?
If so, disable it and try.

Are you using containers?

[Fringetastic]

I am not using containers. Clean URL was enabled. I've now tried with Clean URL disabled and I am able to login.

[erosman]

Clean URL can conflict with sites that pass data via URLSearchParams.
It will be reworked in the next update.