Disabling Buffer Extension Stops Safari Window Resize

For awhile now, I’ve been dealing with a minor annoyance. When I go to box.com, my Safari 7 window resizes itself.

Googling didn’t produce a solution, until someone suggested disabling/enabling extensions to find out if one of them was the culprit. Much to my surprise, the Buffer extension seems to be the causing the problem. When it is disabled, the browser window doesn’t resize on box.com.

I have no idea why this works, or even if it’s the same for everyone. Just that disabling the Buffer extension solved my problem.