Chrome DevTools 100% CPU

Strange, i've been struggling for days, and i found the solution right after asking here..
some days ago looking inside DevTools Settings -> Workspace i set a local folder.
now i have unset it and the CPU issue vanished!
good!
but can someone explain me what happened?

I had the same problem (100% cpu utilization when I hit a break point) and disabling the Chrome Workspace mapping did not resolve my issues.

I tested it in Firefox and found the same behavior.

I think the problem is caused by Flash plugin. I disabled flash plugin in Chrome and it stopped the problem. But caused another one which prevents me from actually hitting any breakpoints.