Steps to reproduce

1. create a multi branch pipeline
2. go to classic, favourite the Folder
3. go to Blue Ocean and try to remove it as a favourite

What should happen
A favourited folder should never show up as a favourite in Blue Ocean

Original request
I am only able to reproduce this with one specific Pipeline on ci.jenkins.io, and I'm not sure why.
I think I might need to pair with tscherler again to debug this.