Whenever you need to freeze your website and check its state, you can trigger debugger at any given point.
Let’s say you want to check which classes are passed when element is hovered - move your mouse over it and trigger debugger. The page will freeze and you can browse the dom tree freely.
According to Google Chrome’s DevTools documentation:
Pause script execution (if currently running) or resume (if currently paused)
You need to have your DevTools opened