Maybe this?

gaearon · gaearon · commit ceaa72935358 · 2023-03-19T21:30:48.000Z
diff --git a/vercel.json b/vercel.json
@@ -85,7 +85,7 @@
       "permanent": false
     },
     {
-      "source": "/:path*(?!google)(\\.html)",
+      "source": "/:path*((?!google)\\.html)",
       "destination": "https://legacy.reactjs.org/:path*.html",
       "permanent": false
     },

Original file line number	Diff line number	Diff line change
`@@ -85,7 +85,7 @@`
`85`	`85`	`"permanent": false`
`86`	`86`	`},`
`87`	`87`	`{`
`88`		`- "source": "/:path*(?!google)(\\.html)",`
	`88`	`+ "source": "/:path*((?!google)\\.html)",`
`89`	`89`	`"destination": "https://legacy.reactjs.org/:path*.html",`
`90`	`90`	`"permanent": false`
`91`	`91`	`},`