[2021] cannot build a road into a house across double (width of 2) canal

drag a road to the left across the canal, on the bottom it works across the 1-tile-wide, above on the 2-tiles-wide it fails (when the house is next to the canal, which it is not in the screenshot)

you need to move the house away so that it's not adjacent to the canal, build the road so that a single road tile is created on the other side, then you can delete that useless tile and move the house back next to the canal; once in position, the house recognizes the road fine

to make this even more confusing, what you can barely see on the top is the skyline tower, to which you CAN create a road just fine across the 2-tiles-wide canal (skyline tower seems to be the exception, e.g. trying with sawmill will fail, just like a house)

also, why is the road-across-canal limited to 2 tiles in the first place?