Strange circular USB icon in Finder I've got a minor problem which has been irritating me for some time. Whenever my Mac has a USB storage device mounted in Finder, it shows a circle instead of the usual USB icon. 

I'm not sure when this started (Mac is running 10.14.4 at the moment), but it is consistent with all storage devices and it's strange because the icon appears normally both at the top of Finder and on the Desktop.

Please see the images below for clarity:





Does anyone have any idea why it is the case that this strange circle appears as the icon in the side bar for all USB storage devices? 

If so, is there a way I can restore the standard USB icon you would expect (and can see at the top of the Finder window)?
I have those now, too. I assumed the sidebar icon had just been changed to those circles in a recent update. 



As far as I know, the default sidebar icons are still located here:

/System/Library/CoreServices/CoreTypes.bundle/Contents/Resources/


You should be able to swap any or all of them out for any icons you want. Just give your new icon the same name as the one you are replacing and make sure it is a .icns file. You will probably need to disable SIP in order to do this. 

EDIT: On closer look, I don't see any dots amongst the default sidebar icons in CoreTypes. I wonder if it may have something to do with disk permissions....