How to unload user track icons from project?

Hi,
Is there a way to make Cubase forget about user track icons that we try but then we decide to delete?

I’ve tried some track icons I’ve found online, but then I decided not to keep them.

The thing is I saved a project with those icons inserted, and now every time I open that project Cubase keeps asking me about them.

It’s Elements 9.5.41

Thanks.
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