Disassemble wall (on 2nd floor) destroys floor first

[Cinderwolf]

Just working on some carpentry and replacing walls with window frames, I've discovered that disassembling the wall (clicking on the wall to disassemble) will have my character destroy the floor tile itself. Only after that is destroyed can I disassemble the wall itself.
When the floor tile was removed, the game replaces it with dirt (because it {for some reason} deletes the original texture).
Now when I rebuild the floor, the game does not replace the dirt texture- it just gives me an invisible floor.
I've tested the disassembly multiple times to make sure I was only clicking on the wall itself, even attempting to disassemble a wall frame (that shows me upgrade options to wall or window), still sees the floor destroyed first.