[SushiHippie]

They have a (broken) setting under the accessibility settings which disables all the character key hijacking.

https://github.com/settings/accessibility

But for whatever reason this only seems to work temporarily (if it is already toggled off for you, you need to enable it again, save preferences, then toggle it off, and save preferences) and then it does not hijack '/' for a few minutes.

[klez]

But even then I shouldn't need to do it for every website that does this.