I think, but im not sure, that after i imported the dummy content the customize page doesnt work anymore.
Its a blanc page …
Does anyone know what happend and howto restore it?
I dont want to remove all the dummy content because I made some changes to a page and slider and I want to keep that.
It’s weird for me because i never facing this kind of issue on my side. If you get the issue again, please try to enable WP_DEBUG mode on your website to show the error message. You can check this article about enable WP_DEBUG here https://codex.wordpress.org/WP_DEBUG