to test the range of drones with different fuel, i had built a long road as a large serpent, going back and forth for 8x64 tiles, and with a requester depot at its end. when the first drone started supplying fuel to the depot, and then the requester drone started getting items, they all didn't follow the road, but took shortcuts diagonally across all stripes of roads and vanilla floor.

my guess : the mod tries to even out diagonals by adding a little besides the road, and when two such extensions meet on a tile the mod recognizes this as a valid connection, similar to what was described in recent FFFs about walking across single-tile-gaps on a path ...

savegame : https://www.dropbox.com/s/gc5s1svc085dxad/diagonally.zip?dl=1

Not a bug :)

thanks for answering.

then we have to separate networks (or tracks that are supposed to make some track longer and thus less preferable) by at least two non-road tiles !? one more argument in favor of getting network IDs to pair up depots on one road instead of needing separate roads :-)