fix: ignore .woff2 and modern static-asset extensions

[marcin-prerender]

The bugs

1. Missing modern static-asset extensions. The IGNORE_EXTENSIONS blocklists predate woff2. Matching is exact on the final extension, so .woff does not cover .woff2. Bot requests for .woff2/.otf/.eot/.webp/.avif assets were routed to service.prerender.io instead of being served directly.

2. proxy.ts: the extension filter was dead code — it matched NOTHING. The extraction

const extension = pathname.slice(((pathname.lastIndexOf(".") - 1) >>> 0) + 1);

already yields the extension with its leading dot (e.g. ".woff"; "" for dotless paths). The code then prefixed another dot:

const dottedExt = hasExtension ? `.${extension}` : ""; // "..woff" — double dot

"..woff" never matches any IGNORE_EXTENSIONS entry, so every bot static-asset request (.css, .js, images, fonts — all of them) was forwarded to Prerender in the proxy.ts integration.

3. middleware.js: case-sensitive comparison. The extracted extension was compared without lowercasing, so e.g. /LOGO.PNG slipped past the filter. The contract mandates case-insensitive suffix matching.

Live evidence

Verified against prerender.io itself: a Googlebot-UA request for inter-*.woff2 returns a 504 (normal UA: 200), while .css/.js correctly bypass Prerender and return 200 for both UAs.

Contract

Canonical change to the static-asset ignore list: prerender/integration-contract#1 — the contract list (case-insensitive suffix matching) now includes .woff2 .otf .eot .webp .avif .webmanifest.

Changes

• middleware.js: added .woff2, .otf, .eot, .webp, .avif to IGNORE_EXTENSIONS; removed the duplicate .doc; extension is now lowercased before the includes check.
• proxy.ts: added the same five extensions; removed the broken double-dot dottedExt construction — the comparison now uses the extracted extension directly (it already includes the leading dot), lowercased. Dotless paths still yield "", which never matches.

Validated middleware.js with node --check; sanity-tested the extraction (/fonts/inter-bold.WOFF2 → .woff2 → ignored; /about → "" → proxied).

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