In case you install a Ultimate Addon for Elementor and get a blank screen/500 error, this article is for you.
Below are the possible reasons for this issue –
WordPress Memory Limit
As soon as you install a plugin the memory allocated by your server for your site might get exhausted. To solve this Increase the WordPress memory limit as mentioned in this article.
Older Version of PHP
Your website server might have an older version of PHP. PHP versions below 5.4 are unsupported by PHP itself. They have come to End Of Life.
To check PHP version running on your site use Health Check & Troubleshooting plugin.
You can contact your host provider and ask them to update the PHP version.
Check Requirements for Elementor
If above suggestions do not help check all requirements for Elementor plugin.
Quick Solution
Try deactivating some plugins from the site as explained in this article.