Hy there,
I have a problem with Elementor since the 3.6.0 upgrade, and even with last update 3.6.4.

I have this notification on the pages that are built with WooCommerce Page Builder for Elementor :

Deprecated: _register_controls is deprecated since version 3.1.0! Use Elementor\Controls_Stack::register_controls() instead. in /home/royaltyf/domains/royaltyfreepiano.com/public_html/wp-includes/functions.php on line 5323

See attached printscreen…

It seems that WooCommerce Page Builder for Elementor could is the problem, not Elementor itself.

Thanks in advance for your help…
Cheers
Christophe