Display bug of the icons of a diagram

Hi,
i have an issue on a Capella model, I was making diagrams on a capella project from a capella librarie, and at once, all icons became grey like in the picture. Anyone knows why ?
I was doing this in Physical Architcture.

Thanks for any help !

Quentin.

Copyright © Eclipse Capella, the Eclipse Capella logo, Eclipse and the Eclipse logo are Trademarks of The Eclipse Foundation.