Mortise (opens in a new tab) 1 min read
When to re-baseline Mortise after URL changes
After a planned redirect or IA change, fix the new 404s, then take a fresh Mortise baseline so old paths stop counting as regressions.
Mortise alerts when a link that previously returned a success starts failing as 404 or 410. That is wrong only when you meant to retire the old URLs. After an intentional change, clean up, then re-baseline so the new map becomes the quiet normal.
Situations that need a fresh baseline
- Site or section migration with new permalinks (migration guide).
- Theme or plugin update that rewrites menus and templates (after a theme or plugin update).
- Large redirect map you just finished verifying.
Do not re-baseline just to silence a surprise 404 you have not investigated. That hides the bug.
Order of operations
- Ship the URL changes and redirects.
- Inspect for leftover breaks (SiteCheck free covers up to 25 pages with no account).
- Fix chains and loops if needed — redirect chains and loops.
- In Mortise (opens in a new tab), run a crawl that becomes the new quiet baseline once the site matches what you accept.
- Leave monitoring on. Later crawls should only fire for unexpected new breaks.
Free plan: one verified site, 200 pages, manual check once per day. Pro adds schedules and email/webhook so you are not the only person watching the dashboard.
How this differs from ignoring known 404s
Keeping an old baseline already ignores URLs that were broken on day one. Re-baselining is for when the good set of URLs changed on purpose. Same idea as why broken-link checkers keep reporting the same links, applied after a planned cutover.