thx for size link. still...
If not hidden then:
Using MyFiles (builtin file browser in Samsung) to show storage, lists some folders (usually system folder?) with "dimmed" folder icon. What does it signifies? and how to tell if a folder is "dimmed" or not?
The dot makes some apps think there is no file name, just the extension, and ignore it Pictures starting with a . for example, will not show in most photo browsers.