Microsoft has today announced that its Windows 10 Microsoft Edge browser now supports Brotli as an HTTP content-encoding method. In a blog post today, the company says the support is starting with EdgeHTML 15.14986. That build of Edge has been available for some time, but Brotli support is coming to Windows Insiders first.
Rob Trace, Senior Program Manager, Microsoft Edge says that Brotli support is available in preview on the Windows Insider Program. The web browser supports both HTTPS and HTTP connections. With this new development, Brotli now operates across Google Chrome, Mozilla Firefox, and Microsoft Edge.
Brotli is an open source data compression format, previously based on the WOFF2 font format. It is based on variants of the LZ77 algorithm, Huffman coding, and 2nd order context modeling. One of the key abilities of Brotli is improved compression ratio, which can be up to 20% better. The format can achieve this without losing compression and decompression speeds.
Trace explains how improved compressions help Microsoft Edge:
“This ultimately results in substantially reduced page weight for users, improving load times without substantially impacting client-side CPU costs. As compared to existing algorithms, like Deflate, Brotli compression is more efficient in terms of file size and CPU time.”
HTTPS Connections in the Future
While Edge supports HTTPS and HTTP connections in preview builds, Microsoft will change support in the future. The company says Brotli behavior will be updated to only support HTTPS connections. Mirroring Google's use of the format, Microsoft will keep decoding Brotli for HTTP connections.
Lastly, Trace welcomes Insiders to test the new support in Microsoft Edge and provide feedback. The exec points to one known issue where F12 Developer Tools do not display the accept encoding response header.