Connections to HTTP, HTTPS or FTP servers on port 10080 will fail.
This is a mitigation for the NAT Slipstream 2.0 attack. It helps developers by keeping the web platform safe for users.
Interoperability and Compatibility
Firefox and Safari are involved in the discussion to block the port, so interoperability risk is not significant. Firefox has already shipped a block.
This will inescapably cause problems for developers running servers on port 10080. They will have to move to a different port. We strongly recommend using port 80 for HTTP and 443 for HTTPS to avoid the risk of future blocks.Gecko
: No signal Minor incremental change, so not asking for official position.Web developers
: Positive (https://twitter.com/TypeSong/status/1379603571193249793
This is a security improvement.
The main risk is that we will have to block more ports in future.