When typing code, it seems like every keypress immediately triggers a restart of the app. If you have the logs window open you’re constantly getting build errors streaming in (while typing, code tends to be invalid until you’ve finished each statement). All this updating seems to cause the browser to frequently lock for periods.
Here’s a screenshot from the Chrome profile tab which shows frames between ranging from 280ms to 486ms while I was typing a line of code.
I’m running on Chrome OS (Chrome 49, 64bit) on a Dell Chromebook 11 with (Celeron 2955U, 4GB RAM).