I am searching for tool or rules set for searching of unresponsive (or slow) scripts(I guess JS in most cases). Of course it could be browser dependend, coz some unresponsive script in firefox work ok in chrome. Still some materials should exist.
A good code profiler (JS or not) will tell you who started what function call (stack trace or call tree), how long the particular function was running and possibly what resources it is using over time. Some profilers do flame charts which are a great way to visualize resource utilization and latency.
Here is a screenshot from Chrome JS Profiler: