It’s the master compositor, laying all windows out to generate the image to be displayed. It also handles input and other event routing, as it knows where each app’s windows are, and which are at the front.
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Where would you set the default call handler for macOS? And where in System Settings do you set the default web browser?
Some system-wide settings are hidden away in the preferences of bundled apps. Here’s a list of where to look for those and others which aren’t easy to find.
The master compositor of windows, WindowsServer is a key part of the GUI which runs from when the login window appears until your Mac shuts down.
This vital service composites individual windows to form what will be displayed, and routes clicks/taps to the correct app.
Mojave brings new flying thumbnails of screenshots and more options. But do they solve limitations in taking screenshots?
Apple Support has to be wonderful now because there’s hardly anywhere else to go to find out about our Macs and other Apple products.
How the iOS Photos app may save your PNG screenshot images in JPEG format: one mystery solved, another opened.
When you take a screenshot in iOS, it is saved in PNG format. There is no option. So why do mine come across on iCloud Drive as a JPEG?
The Eclectic Light Company 