Troubleshooting

Symptom	Cause	Fix
An image or font is missing from the PDF	The resource could not be fetched and was skipped.	Read `X-Skipped-Resources-Detail` for the reason and URL; see Remote resources.
422 `unsupported_document`	The document uses features outside the Forme subset.	Read `unsupported`, then change the document or render with Chromium. See Forme.
422 `unsupported property: border-bottom-width` (Forme)	Forme does not accept the `border-{side}-width` and `border-{side}-color` longhands.	Use the shorthand, such as `border-bottom: 1px solid #000`. See Forme.
Forme refuses characters (`is not covered by any font`)	No available font covers them, for example Chinese, Japanese or Korean.	Link the Google Fonts stylesheet of Noto Sans KR (Korean), Noto Sans JP (Japanese), or Noto Sans SC or TC (Chinese); register a TrueType font that covers them; or render with Chromium. See Fonts.
422 `is drawn in reverse order by Forme`	Forme draws Arabic-Indic and Persian digits in reverse order.	Use Western digits (0-9), or render with Chromium. See Forme.
A header prints on the first page only (Forme)	`position: fixed` is refused by Forme; a header in the page flow prints once.	Use `@page` margin boxes. See Page setup.
Page content is scaled	A `@page size` is fitted onto the `paper_size` sheet.	Set `paper_size` to match the document's page size. See Page setup.
429	The rate or concurrency limit is reached.	Retry after `Retry-After` seconds and cap requests in flight. See Rate limits.
413	The request body exceeds the plan's limit, or the PDF exceeds 25 MiB.	Reduce the document, or move to a plan with a higher request body limit. See Plans and limits.