I'm guessing that that is so against building regs.
Or maybe they have not put the balcony up yet or had it refused.
I hope they don't have kids living there or that they cannot open fully.
At least it is at normal window height which will prevent a careless step through the opening. It looks like that needed a new window frame and somebody had something spare "what might do". I will make enquiries on this as we found it highly amusing when we walked past it yesterday. We couldn't stop laughing for a good while afterwards.
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