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What is the important aspect to consider when deciding where windows interaction buttons should be placed?
I've been seeing a lot of modal windows lately, some which have the close button in the top right, some which have them on the top left. My guess is that this is because Windows has it in the top right and OS X has it in the top left. What are the best practices for the location of this button? Should it vary based on OS? Or should it consistently be in the top right/top left?