Hi!
( Just participating )
I recently had the same kind of issue, concerning the blank page, and, Elementor widgets weren’t also opening.
For my case, increasing the php memory limit solved that blank page issue.
The server was set the 32M by default but raised to 512MB and it was ok.
define(‘WP_MEMORY_LIMIT’, ‘512M’);
Hope it can help.
Mario 🙂