What does go figure mean in figure of speech?

The phrase "for the birds" means that something is not worth a person's time or energy. No matter what others say, I think this ridiculous plan is for the birds. Let's just buy some new t-shirts...

In your example, window probably means "a period of time when an opportunity was available." But because it's written in past tense, "you HAD a window," it means that the opportunity has passed. For...

It usually means "we figured that".

work it out for yourself- but is use more like well. I means "think about it" go figure!

It means it is useless to attempt to understand it.