[Решено] Backend Does Not Load / Page becomes unresponsive if WPML is active

Background of the issue:
I am trying to load backend pages on my WordPress site with WPML enabled. Disabling the WPML main plugin via FTP resolves the issue, but it returns when the plugin is reactivated. I've tested earlier versions of the plugin, but the problem persists. This suggests it may be a database-related issue, as the same error occurs locally after importing the database from the staging server and after trying previous and latest versions of the plugin. Link to a page where the issue can be seen: скрытая ссылка

Symptoms:
When WPML is enabled, loading any backend page does not work. The backend page won't finish loading, and the browser will alert that the page is unresponsive.

Seems to be similar to this support ticket raised earlier this month: https://wpml.org/forums/topic/after-update-wpml-backend-doesnt-works/

Questions:
Why does the backend become unresponsive when WPML is enabled?
Could this issue be related to the database?