Double check for memory leaks

With all of the looping, and event listeners in this extension, it's very easy to see how a memory leak can be applied. I need to go in and do a quick audit and make sure everything is exiting correctly, and we're cleaning things up appropriately. Luckily no reports of any major performance issues yet.

Things to look for...
- Exiting loops as soon as possible
- Chrome event listeners aren't being called more than necessary, especially being defined inside react components
- Removing event listeners