Window feeders - will birds fly in to the window?

Hi Hugh, I had one of these for a short time on the kitchen window but soon took it down, because of the mess. It had been wet but the seed was thrown and stuck on the glass and frame not to mention the poo on the white window frames as well! It was only up a few days so can't really say regarding if it would encourage birds to fly into the window.

We have 2 window feeders at home and one on our static caravan. Once they get used to them they are fine, ours are used mostly by tits, finches and sparrows. The collared doves like to have a go too - and yesterday Mr Squirrel was found sitting IN the feeder having his breakfast...