Select2: non existing images requested (from css?)

/loading.gif, /select2.png, /select2-spinner.gif etc

Are we sure that we overwrite all CSS selectors?
If yes, this might also be a client errors (strange client, picking up wrong selector (from `select2.css` instead of `jquery.select2.less`?)
How about we delete those selectors from .css which we overwrite in .less?