Drone video coming out of the Kharkiv region shows the destruction of Russian position inside of a tree line. The fire mission was carried out by Ukraine's 40th Artillery Brigade.

Even when the Russians utilize proper top-cover to conceal their positions, the Ukrainians are still able to spot them. I doubt that this position was spotted by regular drones however. It's more likely that drones equipped with FLIR capabilities spotted the heat signature of this position, and then regular drones maneuvered nearby and spotted it through the canopy of the tree line the Russians were using for concealment.

Proper military camouflage netting has the capacity to block out IR heat signatures. The Russians apparently don't have access to that yet.