Migration issues with Custom Fields

I am having trouble with the WYSIWYG Editor in ACF Custom Fields. After a migration with Migration Guru from one domain account to another (Same Hoster but different domains and differently sized hosting package) the editor of one page only shows the tagged HTML Version within the visual editor tab on the migration target site. All other pages and posts work fine on both sites.

On the migration source site everything works fine with all plugins activated. I tested to deactivate all plugins on the migration target site and I managed to get the custom WYSIWYG-Editor fields working propperly (Showing formated text without tags) again. But as I tried to figure which plugin is colliding with the ACF fields, I discovered that it is not one single plugin, but it is rather the amount of plugins activated. So I tried different combinations of plugins. It showed that there was no plugin which generally triggered the error. With only ACF and another plugin activated all plugins work fine with ACF. But as soon as a curtain amount of plugins is activated, the editor switches to the falty display. And it is also not the simple number of plugins, as sometimes I have 4 activated and then the editor switch happens and sometimes I have more activated before the switch happens. So in my eyes it looked like some kind of buffer or memory limits are triggered and that′s why it switches to HTML. But that′s just a wild guess.

So now I am stuck here.

Any ideas how to fix this?

Thanks!

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