How to change "LOCK SCREEN" background picture. (Not to be confused with the "LOGIN WINDOW"). Help me to do it.
Hello
Please help me to change the grey background of the LOCK SCREEN for a custom picture.
(iMac 2010 w/ High Sierra)
The LOCK SCREEN comes to ask for the password after you select "Lock Screen" from the menu or to access the Desktop after it's locked automatically after certain time or an active screen saver.
The LOCK SCREEN has no Power Off button, and has a plain grey background.
THIS IS THE -LOCK SCREEN-
The LOGIN WINDOW instead, has a blurry version of the Desktop picture. And often confused with the LOCK SCREEN.
It shows either when one chooses from the drop down Fast User Switching menu or the menu > Log Out <User>
THIS IS THE -LOGIN WINDOW- (before and after you select the user to Login)
I have managed to change the the background of the LOGIN WINDOW for one of my liking (same desktop picture but not blurry) just by switching the file /Library/Caches/com.apple.desktop.admin.png
But changing the background of the LOCK SCREEN has been a huge challenge. I haven't found any information on internet on how to accomplish this.
It's been asked many times here and elsewhere, yes, but not answers or not relevant answers, as they often refer to the LOGIN WINDOW, not to the LOCK SCREEN.
I hope that asking (again), but in detail, can bring an answer to this query.
Is there a way to change the LOCK SCREEN grey background for a custom picture?
(Preferable: doesn't require a 3rd party app - Required: not disabling permanently SIP)
Thank you very much in advance.
iMac 27″, macOS 10.13
