[2.0.11] Belt not replaced when using an underground belt when interacting with ghosted belts

[pantabo1]

What did you do? - placed a smelter blueprint on top of the already existing coal belt and then placed the underground going up.
What happened? - the coal belt going north did not get "picked up" by the underground.
What did you expect to happen instead? It might be obvious to you, but do it anyway! - i expected the ug to "pick up" the leftover belts
Does it happen always, once, or sometimes? - it happens always as far as i can tell. i tested it in multiple directions and placing orders, be it first the ghosted belt and then the belt dragged to then place the ug.

[robot256]

FWIW, this still happens in 2.0.24. Probably not a bug. The underground-replacement logic probably thinks that you intend the ghost belt to side-load the belts that remain in between the new underground belts, since it doesn't know the order the belt and ghost were built in.

If you had super-force-built the smelter blueprint, it would have put undergrounds in the coal belt and placed the horizontal ghost belts across it.

[boskid]

I am not considering this to be a bug. Underground belts remove belts only when those belts in between are "simple" that is: they have the same direction as the underground and there are no incoming side connections. Since you have incoming side connections, those belts in between are not a candidates for removal.