- factorio_bug_cliff_removal_1.jpg (53.63 KiB) Viewed 3122 times
In the above case, as I wanted the cliff to be part of my wall, I moved the bp one tile to the right, so the cliffs are not shown to collided with the wall pieces in the bp. Then it shows me this:
- factorio_bug_cliff_removal_2.jpg (59.59 KiB) Viewed 3122 times
But when I place the bp, the cliff still is marked for destruction. Like seen here:
- factorio_bug_cliff_removal_3.jpg (61.69 KiB) Viewed 3122 times
I would expect the cliff to be shown as still colliding before placing the bp or the cliff not marked for destruction after I place the bp.
This is not much of a nuisance in most cases, as one would like to remove the cliffs anyways. Just in case of a walled defense line it is, as cliffs are used as indestructible "walls".
I encountered this a lot of times already. To an extent, that I reverted to build manually close to the cliffs. I just never made the effort to write a report. But this time I died shortly after
and when reloading the autosave, I remembered that this time I have the perfect save to show this. 
