Issues with view blocks in the content region on the view page

Problem/Motivation

I'm developing a website using Classy as base theme, and when I needed to add a block view to a page view, it starts to show some bugs.
This only occours when I add the the block view in the same region content that page view are rendered.

This problem happens in versions 9.3-* and 9.4-* with classy based themes.

This problem does not occur when I use Bartik as base theme.

Despite the views works, I got issues in EU Cookie Compliance module, in the page view (with view block in content region) shows the following errors:

In Firefox:

Uncaught TypeError: drupalSettings.eu_cookie_compliance is undefined
http://192.168.56.101/modules/contrib/eu_cookie_compliance/js/eu_cookie_...
http://192.168.56.101/modules/contrib/eu_cookie_compliance/js/eu_cookie_...

In Chromium:
Uncaught TypeError: Cannot read properties of undefined (reading 'cookie_value_disagreed')
at eu_cookie_compliance.js?v=9.4.5:18:74
at eu_cookie_compliance.js?v=9.4.5:1522:3

In Superfish module, the responsiveness that change menu to hamburger menu stop working

These errors happen when I create a page view and add a new block view in the same content region in themes that use Classy as base theme.

Does Bartik has any function to make view module work or does view module depends on some code in theme to work correctly?

Steps to reproduce

1. Install Drupal 9.x
2. Create a simple classy based theme
3. Create a page view
4. Create a block view and add this block to the content region on structure/block layout.
5. Install EU Cookie Compliance and look at java script console in page view
6. Install Superfish and test the responsiveness, the menu will not switch to mobile version
7. The problem go away if use bartik as base theme;
8. The problem go away if move block view to other region then content region (because the page view is rendered on 'main system block' on content region).