The latest beta version of macOS Mojave adds inside a surprise for developers and is that in addition to all the improvements and bug fixes implemented it adds a new dynamic background, called Solar gradients.
In this case it is a background that simulates the sunrise from below and little by little the entire screen clears according to the time of day we are in. All this obviously with background changes in real time and in true Apple style.
Here you can see the small window effect in a video and to advance task you can advance the video to minute 1:00 which is when you can start to see the effect:
The truth is that personally I like the one of the dune in the Mojave desert much more since you really see "something" on the screen, but like everything in life to taste colors. In this case it is a fairly simple new fund and it is almost certain that in the next versions we will continue adding more funds of this type. All this are simply small changes that do not really affect the whole system and that are obviously not big changes but that add an extra to the system presented by Apple. Hopefully between now and September, which is when the version for all users will be officially launched, we will have more funds of this type to be able to use on our Mac.