Applying "CSS+JS" breaks the steamwebhelper on the latest families beta

[Kennyluzz]

Today I updated to the Steam Families Beta client and the JS tweaks no longer work. I tried using Old Glory with the old method and Millennium, which refuses to work even with different skins while the JS is modified. I did everything in the troubleshooting/known issues sections, even reinstalling Steam completely. I also tried both a clean version of up-to-date OldGlory and my edits that work fine on the non-beta branch. I also realize that this is a beta client and stuff might break but I assume this might affect the stable release when it eventually arrives.