Map Editor Assets not loading

[GabrielLovesLife]

Hello there,
Recently I started making maps for Euro Truck Simulator 2. One day I started the editor and everything I placed for example roads, signs, buildings etc. Were not there. If I clicked on F5 it showed me that there is indeed a road in that location but the road wasn't physically there. If I open my content browser, none of the assets are loading in. It's just a white screen. Can somebody please help me?