Why is debug sometimes buggy in Idea?

Question

Java

I often encounter such a situation when, with debugging enabled and a breakpoint on the code, the site page hangs on loading, but nothing is displayed in the debug window and the idea does not react in any way. One has only to turn off the debug, as the page is successfully loaded. The situation is solved by restarting the server, but this is not always an option. Does anyone have something like this? What is this glitch and how to treat it?