In a previous version, I got in the habbit of using the Steam overlay to take notes, especially keeping to-do lists for the vessels I built. In this version, I find that every time I close the Steam overlay, some sort of console pops up.
I changed the keybinding of the Steam overlay, but it continued to happen, so I changed it back. My normal keybinding for the Steam overlay is Ctrl-/ . The alternate keybinding I tried was Ctrl-; . (Right-Ctrl in both cases.)
This hasn't happened in subsequent launches of the game. It was entirely repeatable during the session in which I reported it, but the next 2 times I launched the game, it hasn't happened at all.
I wonder if I hit some other key(s) the first time I opened the Steam overlay in that session. How that would get the console toggling with the overlay key, I don't know.