PRELOAD_DESCRIPTOR_INVALID
registerAsset("preload") descriptor broke a field rule; link dropped or field ignored (dev).
What you saw
- Kind:
head - Severity:
warn(code that works but is structurally wrong or expensive)
The console report opens with [PRELOAD_DESCRIPTOR_INVALID] and the message, then an in line naming the owners that enclose the subject, root first, and an at line with the source location when the code was compiled with one.
In a captured artifact the same finding is an event with code: "PRELOAD_DESCRIPTOR_INVALID", ownerPath, and loc.
Diagnostics explains each line.
Why it fires
A registerAsset("preload") descriptor broke a field rule (data.field names it — a missing as, a non-string href, a malformed imagesrcset) and the link was dropped or the field ignored.
The server runtime reports on the same channel, with the same in <App> › <Page> line.
Two groups.
Findings (SSR_RENDER_ERROR_CONTAINED, SSR_SUBTREE_ABANDONED, SSR_STREAM_ABANDONED, LATE_HEADER_WRITE, DYNAMIC_ASYNC_COMPONENT, SERVER_ERROR_SANITIZED, FRAME_MARKER_CORRUPTED) are facts about a render that exist in observe builds too — an APM sees them in production; in dev they print.
Checks (the rest, SSR_BOUNDARY_WATERFALL and SSR_CLIENT_CONTENT_MASKED included) are dev-only guidance.
A captured artifact from a server render carries both.
How to fix it
Fix the descriptor at its source; the values are usually the bundler manifest's.
In tests
captureArtifact from @solidjs/diagnostics runs a scenario with the diagnostics channel open and returns the events it saw.
expectNoDiagnostics(artifact) fails while PRELOAD_DESCRIPTOR_INVALID is among them, with the events as evidence; after the fix, the code is gone from artifact.diagnostics.
Check for regressions in tests shows the loop and the Vitest matcher form.
Learn more
- Diagnostics: every code, with its kind, severity, and trigger.
- Debugging reactivity: how to read a report and what each group of codes points at.