Github pages unresponsive after elapsed time

When browsing Github, some pages become unresponsive after being left open for a while. The page will initially be blank. Reloading the page throws a “Page has become unresponsive” error. Clicking “Wait” does nothing. Page never reloads properly. Clicking “Cancel” causes an “Aww snap” SIGTRAP error.

Clearing cache doesn’t change anything. Only happens with Github pages (so far).