Memory limit in Elementor Pro

Hello,
I’m building my first website (apart from some HTML exercises), and considering I’m only using basic shared webhosting, I probably overdid it regarding Elementor Pro features. Anyway, I’d like to understand the issue before I move any further.

I’ve built a somewhat extensive landing page and it worked without issues for about two months. As I kept adding little bits here and there, and optimizing graphics for responsive view, however, the editor suddenly stopped saving any changes with 500 internal server error, caused by reaching my host’s fixed memory limit.

I tried deactivating plugins one by one until I was only left with basic free version of Elementor and that’s the only point where I managed to make the editor work again. I could go on without any other plugins but Elementor’s Pro features are essential for my page. But the moment I activate it, even when I’m not actively using any of its widgets, I reach the memory limit again.

Finally the question: How is the the site and the plugin specifically hogging up all 256M of the allowed memory? Is there any way to tell what is causing it and to stop any unused background features? I can ask for temporary upgrade of memory limit but it’s a one time request and I don’t know which settings to change so I’m not stuck with the same error once the limit is reset to the default value.
I’ll be most grateful for any general information about the cause so I can better understand the issue, as 99% of all my google results only deal with blindly upgrading memory limit, not optimizing the website or dealing with the issue itself.