Editor Only Resources

Hi,
Yes, those images don't need to be included in the project.

In the next version I'm about to release, there is an option to move them to the "Assets\Editor Default Resources". That way they are not included with the builds.

However, not everyone likes having dependencies outside the plugin's folder that's why its going to be optional.
Its a shame that Unity don't allow having a "Editor Default Resources" anywhere else than in the Assets root.

For the moment, you can either delete them as they are only used for the Plugin Manager window (About window) or Manually move them into "Assets\Editor Default Resources".

Hope that helps,
Frank