Run and Review

Start a run

Open a suite and choose Run test. viz queues the run, the worker screenshots every tracked page, then compares each screenshot with the current baseline for that page and viewport.

While a run is active, the run detail page streams logs and progress.

Read the result

There are two separate things to look at:

• Run status says whether the worker executed the job.
• Review state says whether visual changes need approval.

Visual differences do not mean the run crashed. A run that completed but found changes should be treated as changes to review, not as a broken test run.

Review a changed page

Open the run detail page and inspect the diff. For each changed page, compare:

• the current screenshot
• the approved baseline
• the generated diff image

If the change is expected, approve it. For manual and branch runs, approving updates the baseline immediately. For pull request runs, approval unblocks the GitHub check, and baselines are promoted when the PR is merged.

Approve all changes

Use Approve all changes only when you have checked the run and every changed page is expected.

This is useful after a deliberate visual update, such as a footer redesign across many pages. It is not a replacement for review.

Re-run errored pages

If one page errored because of a timeout or temporary network issue, re-run that page from the run detail view. viz re-tests only the errored viewports for that URL and leaves passing or changed results alone.

When to investigate

Investigate before approving when:

• a page changed but nobody expected it
• only one viewport changed in a strange way
• the diff is caused by live data that should be hidden with custom CSS
• the run failed because every page errored