When did this start happening? What is the last thing you did before noticing this issue?
It Used To Happen Sometimes And I Used To Refresh Page To Get Rid OF It…But Now It Keeps Loading And Preview Never Loads.
Try disabling your plugins one by one and check the customizer after each disable. If it loads after disabling a certain plugin then you just might have found your problem.
I Already Tried Deactivating All Plugins.
Reinstall wordpress from the dashboard.
Top left hand corner, it says dashboard, hover over it, it should say home and below that you will see updates, click update. You will see re-install now. Click it and there you go.
Same here! In my opinion, there seems to be a bug in the latest wordpress version. I tried to reinstall AND use their default themes and still unable to access the CUSTOMIZE page. What I see is it attempting to load, but the loading ball just keeps spinning.
One Temporary Solution That Worked Finally…
I Deactivated All Plugins For One Day..Than Other Day…i activated All Plugins One By One And checked Customizer With Every Plugin Activation…Note Down Some Plugins That Caused Problem And Customizer Worked Fine..Also I Removed All Unnecessary Plugins..I Also Searched For The Solution Insanely..I Was Frustrated Of It..
