In the current state, I don't think it would be accurate to say that Qt supports the browser platform, and given the fundamentals of their approach (webGL), they're unlikely to get to an acceptable level of support any time soon.

Someone else brought up legacy codebases, which I can see a use-case for. I could also see a use-case for letting people do design reviews on your native app without forcing them to install a new build.

But would anyone here feel comfortable shipping this kind of output as a commercial product and advertising that your app had web support? I wouldn't.