The blue map border of my minimap is gone...

Can't upload the image right now. As suggested in the title, previously the minimap showed blue lines on map border or the border of the discovered area, but now it is gone. It is very inconvenient in undergrouond areas like caverns and I keep running into walls because the border of cavern maps is not shown in minimap.

In areas like strand, I could see water surface on minimap before, but now it is gone as well.

In options > UI, there are two map transparency settings. I forget which one it is, but it sounds like you have one of those turned all the way down. Turn it up and the border will be visible.