Here is something not many people know: an open application window consumes more memory than a minimized window. You can use that in your benefit: if you have a lot of memory in your PC, you might want to keep all windows open to be able to switch faster between applications. On the other hand, if you work on a PC with little memory, it is better to keep as many windows minimized as possible to free memory for the current application.
Minimizing windows
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Jeroen Sangers
@jeroensangers