I minimized a couple of markets (minimized button circled in red), but how do I get them back?
To get them back you need to run the search and find the market you've removed from favorites (or "minimized" as you call it) and add it (or "maximize") again to your favorites.
While doing the search be aware that the search currently does not work as it should, i.e. you need to enter the full name of the asset you are looking for.
So you need to know exactly what you are looking for, which is very user-unfriendly.
If I recall it correctly, svk once said he was waiting for an issue in the back-end to be solved before he could fix it. And when it's fixed, entering just a few initial letters will do the trick.