Visual regression testing snapshots the UI and compares each new render against an approved baseline. The hard part isn’t spotting differences — it’s telling a real regression apart from harmless sub-pixel noise.
Pick a scenario and watch the diff overlay light up. Switch between pixel-exact and perceptual comparison, then tune the tolerance and threshold to see how the same change flips between PASS and FAIL. More patterns live in the recipes.
Baseline
Candidate
Diff overlay