• Bug: it destroys all your code on bad connection

I was writing a solution with some long pauses in between, slowly and patiently. Then I pressed 'run and check', and it said something about gateway, destroyed all my code and showed the task home page with 'only authorized users can solve things'.

Back button normally should show previous page with filled forms. Instead, your site on going back redirects you to the same task home page with the same warning.

A good practice in such cases is to auto save task code into local storage each minute and restore it when something unexpected happens. Another good practice is to ask for login/password and then continue user's action when session is out instead of showing 'you are doomed, go to home page, ha ha ha'.

And by the way, selecting text in this form is probably 'nice' but not usable, on bright displays you can hardly see the difference between selected text and normal one. Why do you invent a square wheel when marking selected text with a colored bg is a standard?