Functions that modify elements should check if nodes exist

[itsrachelfish]

If a function modifies the DOM using a user provided element, the function should check if the element exists before cloning it. For example, append and prepend currently always clone an element before putting it on the page. This is convenient when adding an element to the page multiple times, but it can be annoying when trying to bind events.

This applies to .append(), .prepend(), .html(), and .replace()

https://developer.mozilla.org/en-US/docs/Web/API/Node/contains

[itsrachelfish]

👍 this just tripped me up again in a new project, it's pretty annoying