I've been utilizing the customizer and as of late, I have been seeing loading issues. So if you click on the "Customize" link in your appearance, that is when the page will stop responding for like 5 seconds and then it loads..This also causes some JS scripts to fail...
This did not happen before when I had a few controls. As I added more, the page loaded slower and slower to a point where you would think something went wrong from a user's standpoint.
So I began investigating and sure enough if I remove like a hand full of controls, the page would start to load fine. Initially I thought maybe it was a specific control that was causing the issue but that is not the case because I removed each one separately to test for this.
I have around 160 controls btw...
So my question is for those of you who is using the customizer api, have you had this issue?