fix: ignore modern static-asset extensions#17
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Add .woff2, .otf, .eot, .webp, .avif, and .webmanifest to the static-asset ignore list in the RewriteCond, per the canonical list in prerender/integration-contract#1. Also deduplicate the repeated \.doc entry and add the [NC] flag so uppercase URLs (e.g. /FONT.WOFF) no longer bypass the filter. Forwarding these asset requests to the rendering service surfaces crawler-visible 504s. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
OpsBeaconCharles
approved these changes
Jun 12, 2026
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The bug
The static-asset filter in the
RewriteCond %{REQUEST_URI}negative lookahead is missing modern asset extensions. When a crawler requests a font or modern image format, the request is forwarded to the Prerender rendering service, which rejects static assets with a 504 — so the crawler sees a 5xx on an asset that serves200for normal users.Live evidence
Verified against prerender.io's own site: Googlebot UA requesting
inter-*.woff2receives 504, while a normal UA receives 200. Any forwarded font/image request surfaces as a crawler-visible 5xx.Canonical reference
This propagates the canonical static-asset ignore list from prerender/integration-contract#1, which adds
.woff2 .otf .eot .webp .avif .webmanifest.Changes (
.htaccess+ the same snippet inREADME.md)\.woff2,\.otf,\.eot,\.webp,\.avif,\.webmanifestto the extension alternation.\.doc, which appeared twice in the list.[NC]flag to theREQUEST_URIcondition — the user-agent condition above already uses[NC], but this one didn't, so uppercase URLs (e.g./FONT.WOFF) bypassed the filter and were forwarded to the rendering service.Caveats
\.woffalready incidentally covered.woff2and\.avicovered.avif; the new entries make the intent explicit and match the canonical contract list. Anchoring (and the resulting over-matching trade-off, e.g.\.docmatching.docxpaths) is out of scope here.🤖 Generated with Claude Code