Minimized pages no longer pop open when the app icon is clicked?

It used to be that if you minimized every window open on the desktop and then you clicked the application icon of any open application, the last window you minimized from that application would automatically pop back open.

Now it doesn't.

And it's not just a glitch on MY machine, I have an iMac at work and it functions the same way, same with my husband's iMac.

Is there a setting that's now defaulted to the "don't automatically open the last minimized window" option? If so, where do I find it and can it be changed?

Thanks!