Modularize and extract crashOverlay to iframe (!1842) · Merge requests · Meta / create-react-app

Merged Administrator requested to merge github/fork/Timer/redbox2 into master Mar 17, 2017

Created by: Timer

This PR includes a highly refactored version of crashOverlay that was typed via flow and then compiled back down to ES5. This refactor enabled rendering into a desired document & element, which made for an easy transition to an iframe (removing some global side-effects and global scoped vars in the process 👍). The overlay was switched to an iframe so that app styles do not have an effect on the overlay.

~~Besides the refactor, this PR also welcomes showing React warnings (#1746 (closed), captured via console.error) and fixes #1853 (closed).~~

~~React warnings still need to be displayed differently to show that they're not errors.~~