If you must go with a pop-up, I’d stick with target="_blank" – and just get over the fact that you won’t get to control the size.
Even without pop-up blockers, there are still people that have JS disabled. I’d also guess that percentage of people using pop-up blockers will continue to increase.
I never messed with it, but I’d guess that the best way to do what you want would be to have an inline player embedded in the page somehow – maybe someone else can offer more info on that.
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