Is Brotli compression supported for instant games?

GZip compression seems to work fine but when I try to test the Brotli compressed build, I get these errors:

Failed to parse binary data file Build/webgl-fb2-optimized3.data.br (with "Content-Type: application/octet-stream"), because it is still brotli-compressed. It should have been uncompressed by the browser, but it was unable to do so since the web server provided the compressed content without specifying the HTTP Response Header "Content-Encoding: br" that would have informed the browser that decompression is needed. Please verify your web server hosting configuration to add the missing "Content-Encoding: br" HTTP Response Header.

webgl-fb2-optimized3.loader.js:1 Malformed data? Downloaded binary data file Build/webgl-fb2-optimized3.data.br (ArrayBuffer size: 32704794) and browser should have decompressed it, but it might have not. Dumping raw HTTP Response Headers if it might help debug: