Yahoo: still learning ReactJS ... - Deploying a dev build to a live website
For frontend web developers, there is a handy Chrome plugin, to inspect the state of the ReactJS website. However, a disadvantage is of course that just about any other ReactJS dev can also inspect your public website. If you happen to have deployed using a *dev* (internal, not really optimized for production) build, then this can be detected by your users. Unfortunately Yahoo Mail! had this issue for a while (but it seems OK now)... Word to the wise: sanity check your production software now and then!