GlassDoor did the same scroll-locking tactic (so an element zapper like Ublock Origin's wouldn't resolve the issue), instructing me to register or sign in to view any information. So I registered an account. Only, it still covered the screen and locked the scroll position, now telling me that I needed to leave a review for my current employer if I wanted to use the website for information gathering.
I find this particularly egregious, particularly for a company ostensibly founded around the notion of transparency and freedom of information (in regards to workplace compensation and culture). Evidently one is only entitled to make informed decisions after first experiencing the potential consequences of making uninformed decisions. Joyous.
Suffice to say I will not be using GlassDoor in the future.