Fix

beta/.gitignore

@@ -33,3 +33,8 @@ yarn-error.log*
 
 # vercel
 .vercel
+
+# external fonts
+public/fonts/Optimistic_Display_W_Lt.woff2
+public/fonts/Optimistic_Display_W_Md.woff2
+public/fonts/Optimistic_Display_W_Bd.woff2

beta/scripts/downloadFonts.js

@@ -0,0 +1,17 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ */
+
+const {execSync} = require('child_process');
+
+// So that we don't need to check them into the repo.
+// Serving them from the same domain is better for perf so do this on deploy.
+execSync(
+  'curl https://conf.reactjs.org/fonts/Optimistic_Display_W_Lt.woff2 --output public/fonts/Optimistic_Display_W_Lt.woff2'
+);
+execSync(
+  'curl https://conf.reactjs.org/fonts/Optimistic_Display_W_Md.woff2 --output public/fonts/Optimistic_Display_W_Md.woff2'
+);
+execSync(
+  'curl https://conf.reactjs.org/fonts/Optimistic_Display_W_Bd.woff2 --output public/fonts/Optimistic_Display_W_Bd.woff2'
+);