New file error: 'Sibling page failed to parse'

[shikokuchuo]

I have a project, where one of the files contains an error.
Then I create a new .qmd file, the following error immediately shows up:

Sibling page '/project/index.qmd' failed to parse
⚠ /project/index.qmd failed to parse
Line 126: Parse error - unexpected character or token here
Line 126: Parse error - unexpected character or token here

Other existing files in the project do not show this error, even as I modify them.

[cscheid]

That's annoying. We must have inadvertently have a required rendering of index.qmd in the pipeline somewhere.

[cscheid]

We looked into this (triage record: claude-notes/issue-reports/233/triage.md on branch bugfix/issue-233).

The message comes from the live preview building project navigation (sidebar titles, cross-document links): every page in the project is parsed — parse-only, no full render — on each preview render, and one of your files (index.qmd) has a parse error at the indicated line, so the preview reports it no matter which file is open. Fixing the parse error in index.qmd makes the banner go away.

As of current main we could not reproduce the asymmetry you describe (the banner appearing only for newly created files): in our repro the banner shows consistently on every page — existing pages, on switch and on edit, and new files alike. It's possible that on existing pages you were seeing it in its collapsed state (a small "⚠ Error" pill in the corner of the preview), which is easy to miss.

That said, the presentation is genuinely misleading, and your report surfaced two real bugs we're fixing (tracked as bd-3a3ymh26):

1. The banner is styled as a red "Render Error" even though the page you're looking at rendered fine — it will become a warning, matching what q2 preview already does.
2. It prints the internal VFS path (/project/index.qmd) instead of the project-relative index.qmd.

Thanks for the report!