Does someone know if WebAssembly support is available on the open-source Qt?
Also: is it one of those features that is a pain in the ass to set up from CMake instead of QMake?
it is. I know that on windows the toolchain is available directly from the online installer, but I think that it isn't on linux. It's a quick build however :
git clone qt5 https://code.qt.io/qt/qt5.git
cd qt5
git submodule update --init qtbase qtdeclarative
mkdir ../build
cd ../build
../qt5/configure -xplatform wasm-emscripten -nomake examples -nomake tests -opensource -confirm-license -prefix /opt/qt5-wasm
make -jwhatever && make installRemember that WA lives in a black box with nary any access to networking, other APIs etc. and communication in/out of the block via shared memory is very, very low level.
QT is still heavily reliant on QMake in reality, but that should be a small part of the decision equation.