If you climb via the skills menu with sl, or with alt-l, for example along a fence, and you leave one tile type (for example Sea) and enter another (for example your settlement), then the picture at the top will stay the old tile, and the bottom where it says "Sea at Saamakorpi" will continue to say Sea instead of saying "Your settlement". It will stay the old tile until you scroll in or out (with mouse or ctrl + and -) or until you move regularly.
The bug doesn't occur when climbing via moving forward with the up key (with auto-climb fence enabled).
This doesn't affect anything: checks about whether you can zoom out will still succeed, the game knows that you're not really on the water tile anymore.
In this image: the entire fence is actually my settlement, which was a heathland tile, not in the sea tile.