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Please, make the contents of the page occupy the whole page width, or at least make the code windows resizeable.
I don't think this would be a good upgrade to the site.
Keep it simple.
If your code is too long it is already hard to read. Split your code on multiple lines and make it in a readable format. Don't forget we don't want to spend hours trying to figure out what you did.
Stack Overflow have the best formatting tools I've seen on any site and I can think of almost a 100 things I would change before that.
Also, don't you think these informations are relevant ?
I can't think of a way to make the code blocks resizable without killing the whole interface design.
I mean ... really ?