Earlier quoted context omitted.
>I miss proper custom desktop apps with horrible looking cluttered interfaces. Soo productive compared to any web based interface for almost all tasks. You mean where everything runs on the UI thread? Gotta pass on that. :)
But (most) browser apps are single threaded and you can block the UI if you do anything intensive on the client-side.
Edit: Did you mean the browser itself could freeze? That's a thing of the past with Firefox being the last browser to separate the content and chrome process. So the web page may freeze, the browser window itself shouldn't.