Failure to test is why I started to work on ember-container-query.
A few months ago, my team and I introduced ember-fill-up to our apps. It worked well but we noticed something strange. Percy snapshots that were taken at a mobile width would show ember-fill-up
using the desktop breakpoint. They didn’t match what we were seeing on our browsers.
For a while, we ignored this issue because our CSS wasn’t great. We performed some tricks with flex
and position
that could have affected Percy snapshots. Guess what happened when we switched to grid
and improved the document flow. We still saw incorrect Percy snapshots.