Patch Notes for 1.21.1-f9

We have a very small update for you all today that covers the bugs reported to us over the past week. We think that this will be the last one!
This update is very minor and should not affect mods and asset functionality.

• Fixed a bug where trees placed on roads would go back to default trees when reloading the save file.[/*]
• Fixed a bug where trolleybuses became invisible.[/*]