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GoogleChrome · Oct 13, 2017 · dae25d2 · dae25d2
1 parent 488ffdd
commit dae25d2
Showing 1 changed file with 1 addition and 0 deletions.
diff --git a/lighthouse-core/audits/byte-efficiency/cache-headers.js b/lighthouse-core/audits/byte-efficiency/cache-headers.js
@@ -127,6 +127,7 @@ class CacheHeaders extends ByteEfficiencyAudit {
 
     if (headers.has('expires')) {
       const expires = new Date(headers.get('expires')).getTime();
+      // Invalid expires values MUST be treated as already expired
       if (!expires) return 0;
       return Math.max(0, (Date.now() - expires) / 1000);
     }