The blue thing in the top left corner. I'm next to positive it didn't have anything to do with a mission. And I went there and couldn't find anything :|
I am pretty sure it is a marker for a personal teleport device, and item you have in your inventory. It will have the face of the teleporter guy. I think you get like 5. That marker means that you can teleport to that spot from anywhere else. You just right click on the item in your inventory, select the location from the list, and click move. You can also set locations by right clicking the item, and choosing a blank spot, and clicking save.
you have an item that has the face of the teleporter, it's the last place you died or saved here with this item.
If you use the item you can teleport at the blue bubble
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