The term "context object" is being removed from DOM:
https://github.com/whatwg/dom/pull/973

This also changes a reference to <a> elements to the string "a", since
querySelectorAll's argument is a string. This may have unintended side
effects of matching <svg:a> and "a" elements in other namespaces.

• Commit 3a05dd2
• #1582: Editorial: migrate from "context object" to "this"
• Branch master

Philip Jägenstedt