After the footer ends on a Category Page the page continues by being blank/white

Actually now that I continue to work on the website it appears it’s not WPML that’s the issue.
I have disabled all other plugins too, apart from the main ones. None of them seem to be the problem as the issue continues to be visible (the issue with switching pages and mixed up page results). So it may be caused, again (as with the blank page), by the categories. I’ll wait for your response on the issue and how to restrict the main category from opening all the subcategories.
It’s happening because there are a lot of sub categories within one category.
It’s like having a website for cars and the categories+subcategories would look like.. Cars/Audi/Sedan/A4/4-doors/Blue/Actual Product.

1. I want to know how to manage these categories; meaning I want to know how to exclude some of them if I want to, is there an option like that ? Because not all created categories are meant to be in the menu usually.
2. As per your question – it’s needed, because it’s creating issues. That means I need the main category name + 1 more line of sub-categories showing, not more as it is creating problems if it’s more than that. See attatched picture for how much is ok.

1. Yes, I know that, but how do I exclude them from here: Attached Picture 1
2. Okay, I put the code in and it doesn’t display anything else apart from the category. Is there a way to do the same thing but for category + (first) sub category and then not to display anything else or this is the only way ?

Okay, this code is perfect for the job.

Sadly though the problem with loading category pages is still visible. Again I disabled all plugins and with only one it seems this problem to be gone. It’s a plugin called Redux Framework. When I disable it, everything seems to ‘fly’. With it .. it slows down. Meanwhile I see it’s a pretty important plugin for the theme. But that doesn’t matter when it creates problems.
What is the solution for this as this is a theme plugin ?

The problem is that when I click on a category or on a next page of the category I am viewing the website refreshes twice. First time it refreshes with the current content, second time, about 5 seconds later it refreshes with the actual content that it is supposed to display.
I made a video about it: https://youtu.be/jmE5d78SIiw
The same problem, even though not that frequent or with that kind of delay in displaying the results is a website you have listed for your example pages: vog-boutique.com/.
Check 01:10 and 01:34 to see the problem at their site. On mine it’s pretty obvious.

The problems are 1. double refreshing (first of which is wrong) 2. the delay in displaying results. And when you disable this Redux Framework plugin everything is fine. Of course, you can try and see for yourself. I tested all the plugins, only this one creates this problem.

PS: I purchased the theme 1/2 days ago and have done nothing but transfer 3800 products (with their categories) in the website and install some important plugins for me like the w3 cache/yoast/wpml. That’s it.

Okay, thank you for your help and quick answers! This problem is gone now by disabling the AJAX.

One last question and sorry to keep you still activate on the ticket, but out of curioucity and future progress of the website what do you mean when you say ‘slow website’. The quantity of the products or something else ?

Okay, thank you very much for your help!