Assets Validation error

Here you can read more information about the Assets validation errors that the Validation Suite can produce, how to solve them and where to read more about how to solve it.

Image Quality Checks - JPG files cannot be included in a package

Packages should instead use the PNG image format for any asset Unity users are meant to interact with in the editor, or use in their project, which includes samples found in projects. This requirement does not apply to documentation and test code.