Disable PR code comment keybindings

I review PRs in Safari, and up until today, Safari would pass Control-e to the Mac OS, which would move the point to the end of line. Now however, it adds markdown to the comment.

Similarly, Control-b would move the cursor back one character. Now, it adds bolding.

There are other keybindings that GitHub overrides in Safari that have annoyed me for a while (e.g. Control-k, Tab when something is highlighted), but I just accepted it.

But overriding Control-e and Control-b is a bridge too far, as they have consistently worked the same ever since the NeXTStep OS.

So, how can I disable either specific keybinding overrides, or - failing that - disable all keybinding overrides in PR comment panes?

I review a lot of PRs, and these keybindings really mess with my typing.