4.0.0

More details about this release in the blog post: https://socket.io/blog/engine-io-4-release/

Bug Fixes

• react-native: restrict the list of options for the WebSocket object (2f5c948)
• use globalThis polyfill instead of self/global (#634) (3f3a6f9)
• properly assign options when creating the transport (7c7f1a9)

Features

• strip debug from the browser bundle (f7ba966)
• reverse the ping-pong mechanism (81d7171)

Links

• Diff: v4.0.0-alpha.1...4.0.0
• Full diff: 3.4.0...4.0.0
• Server release: 4.0.0
• ws version: ~7.2.1