User-1124897295 posted
I think thats not a cause of problem, because it's not happened with other aspx Pages.
Moreover, its not happened in other projects in this solution.
There is only one aspx.page, in one projekt that has this problem. They has a simple master page, bootstrap, custom css and a content in content place holder Maincontent.
The content is lage and have a several gridViews and capsuled controls inside of gridviews.
But as I said, if I edit or checkut aspx page before i switch between modes, that works nice.
Otherweise came "Masterpage will loading.. " and then crash of VS.
I think, that is a bug of VS, which cannot work with a large content.
If I delete subfolder, as You write, I will have a big problems to get solution working again.