WebAssembly is now supported by all major web browsers as a binary format for allowing sand-boxed executable code in web pages that is nearly as fast as native machine code. Qt for WebAssembly makes it possible to run Qt applications on many web browsers without any download steps or special server requirements (other than serving the wasm file).
To give you a closer look, we compiled some demos. For best performance, use Firefox.
Here is the complete list along with some descriptions: