Apple Adds New 'Hello' Screen Saver in macOS Big Sur 11.3 Wednesday April 21, 2021 5:39 pm PDT by Juli Clover macOS Big Sur 11.3 includes a hidden "Hello" screen saver that appears to be designed for the new iMac models, but which can also be installed on any Mac that's running the 11.3 update. As outlined by 9to5Mac, the new screen saver is not available by default, but with a simple set of instructions, can be accessed on even non-M1 iMac machines. On a Mac running macOS Big Sur 11.3, follow these instructions: Open the System folder. Rename the "Hello" file to something else. Double click the file.