Some people online solved the problem by switching from the Firefox 64 bit version to 32 bit version. I got the same message after I switched to the 32 bit version.
I can use Chrome without any problem on the same PC. My older PC with Windows XP and Firefox has no problem.
I have the same problem, I got a new forbidden message each time I tried to access walmart.com, ie:
Forbidden 1508955657-94-320-64562795
Forbidden 1508955723-94-320-75082305
Forbidden 1508955778-94-320-37991062
Some people online solved the problem by switching from the Firefox 64 bit version to 32 bit version. I got the same message after I switched to the 32 bit version.
I can use Chrome without any problem on the same PC. My older PC with Windows XP and Firefox has no problem.