After building and removing entities some drones will not return to the players inventory.

I originally found the bug in my heavily modded playthrough. I then did a test for the bug using a fresh install of Factorio 0.18.22 and made a save with only two mods using Construction Drones 0.5.4 and Creative Items 1.5.0.

I can replicate the bug by using a blueprint on ore patches. After building the blueprint some drones will not return to the players inventory.

I can then replicate the bug again after using the Deconstruction Planner. Again, some of the drones will not return to the players inventory.

Save File: https://drive.google.com/open?id=1a8OP54ibS5TRn5zONL2BTYpTkTNvHKsQ

I tried a different fix for the next release

Nice catch. Having same issue here, at least I can avoid it now!

Klonans update fixed it on my end. Are you still having issues?

Yeah definitely had issues yesterday, I deconstructed an ore crusher (angels mod) that was built on top of saphirite (bobs mod) and it just disappeared. As you can see, I'm using mods from bobs and angel, also AAI, plus a few others, so maybe thats the reason. Either way, knowing the cause makes it easy to avoid it!

I have noticed that when the drones get stuck they will stop moving and then after a few seconds they disappear and reappear in my inventory.