The file Content://Cz.Mobilesoft.Appblock.Fileprovider/Cache/Blank.Html is supposed to appear empty because that is its job. This is aimed at loading an entirely blank page, such that not even a single thing is depicted. This assists the AppBlock application in substituting or blocking unwanted material with an easy blank screen. There is no text, code, or images inside because it is simply a placeholder file that forms the file structure. This is normal: the emptiness is intentional, and not the symptom of a malfunction of the file, and thus, there is nothing wrong with it.

Know more : http://gadgetbyte.net/content-cz-mobilesoft-appblock-fileprovider-cache-blank-html/