SpriteFont troubles in 3.5

So I’ve been using 3.4 for ages now and when I started working with a friend I gave him my 3.4 project not knowing he had 3.5, this completely broke so I installed 3.5 to see what was up and now I can safely say I have no clue.

SpriteFonts would not load, textures were completely fine, but SpriteFonts just wouldn’t work.

Exception thrown: ‘System.NotImplementedException’ in MonoGame.Framework.dll

Googling “Monogame 3.5 SpriteFont not loading” and the like brought up nothing useful, but I followed the advice anyway and started a new Windows Monogame project (OpenGL), added in a font through the pipeline tool and attempted to load it yet I got the same error. I then started a new Desktop project and tried the same thing, it worked

I don’t feel comfortable moving on with my project without knowing what is causing this bug, so I’m asking here. My guess is that the Windows project is no longer supported in 3.5, but how would I remove old templates?