I would like to program web applications as I do with desktop programming languages, where the code is synchronously executed and browser doesn't freeze when doing loops.

Yes I know there are workarounds using callbacks and setTimeout, but they are all workarounds after all and they don't give the same flexibility when programming in the orthodox way

I've been looking at Dart as a possibilty, but I can't seem to find where it says it can do either of these. The same with haxe, emscript, and the hundreds of other converters that try to circumvent javascript. In the end it gets converted to Javascript so you ultimately have to be conscious about asynchronous/multi threading.