[0.18.1722] Flying roof

[NeverPire]

I have borrowed a computer to make some tests.

Circumstances :
I have deconstructed an ancient danger room to recuperate its metal but strangely some parts of its roof stay present.

What should happen :
The roof should collapse

What happens :
The roof stays in position

Screenshots or savefile :
- Screenshot attached
- Savefile through google drive (https://drive.google.com/open?id=1EzdmXIa6VVtQbl-Gc6EKIYY8gRh7PDw1)

[attachment deleted by admin: too old]

[harpo99999]

my guess at the cause is
1 the 7 tile support from wall/rock/orebody/colapsed rock
2 unremovable roof is usually from thick roof ie mountain overhead

[NeverPire]

I have done some test and when all the supports from a thick stone roof are removed, colapsed rocks always occur to stabilize it.

1) Look at the 4-tiles roof top left, nothing support it.
2) Flying roofs here are of constructed roof built by the map generation above ancient danger wall.
I can have them removed by my pawns but I am of course not capable of rebuilt them in the same position.