This happens with some other websites, but pluralsight is the one I use the most. When going to https://app.pluralsight.com, I get the following results.
On Edge:
On Chrome:
On Firefox:
On my co-worker’s machine, all 3 work.
We have the same network settings. I just reinstalled Windows. I had this issue before reinstalling Windows.
I am at such a loss. I don’t know where to look to even begin troubleshooting this. I know what the issue is (SSL) but I don’t know why.
Check the certificate and see what transport method it is using. Older ones are blocked on certain browsers.
Tried to go to Security > Certificates in Chrome, but got this:
reload to get the main origin
Tried that, it never shows up. I see information flicker for a moment then immediately disappear.
Something about Unknown / canceled with the URL under it. Nothing else changes/shows up.
After some testing in Firefox, I am still unsure what the issue could be. Our browsers are identical. Our network settings are identical. We’re affected by the same policies in AD. This is before even logging into any websites.
I’ve tinkered in Firefox’s about:config section and tried setting max/min TLS version from 1 to 4 (restricting TLS to one specific version each time). TLS 1.0 & 1.1 didn’t work, while TLS 1.2 & 1.3 did.
However, this was in Firefox, where it was already working. Modifying these options hasn’t helped at all in Chrome/Edge.
Tried installing Chrome Beta: 
Turns out it was Microsoft Cloud App Discovery Agent.
Never updated to support TLS 1.2 since it’s going EoL before Microsoft fully switches over to 1.2 exclusively.