Limits and troubleshooting
What a soft navigation step cannot measure, and what to do when one fails.
Limits
- One soft navigation per step. If Chrome reports several, the first is measured and the step gets a run warning.
- No simulated throttling. See Throttling.
- No LCP breakdown insight. Other insights cover the whole trace, as in a timespan.
- A redirect is a page load. A step that changes the URL and then loads a document is measured as a page load.
- Accessibility alone needs a snapshot. A soft navigation step needs at least one audit that uses the trace.
Troubleshooting
| Symptom | Cause and fix |
|---|---|
| The first step fails because the click finds no element | No page is loaded yet. Start the flow with flow.navigate(url); a soft navigation starts from a loaded page. |
The step fails with NO_FCP | Chrome didn't report a soft navigation. The interaction has to be a real input such as page.click, and it has to paint new content. Check that Chrome is 149 or newer. |
| The metric audits error | The step ran with simulated throttling. Pass throttlingMethod: 'devtools'. |
| The step is measured as a page load | The click loaded a document: a link the router doesn't handle, a reload or a redirect. |
| Multiple soft navigations warning | The click changed the route more than once. Only the first is measured. |
user-flow collect --dryRun fails | Dry runs don't support navigations that start with a callback or startNavigation yet. Run without --dryRun; see user-flow#355. |