Merge PR mumble-voip#4522: MAINT(docs): move and improve global short…

…cuts instructions and explanation

README.md

@@ -106,21 +106,3 @@ To load a game with the overlay enabled, start the game like this:
 If you have Mumble installed through the binary packages, this can be done by
 simply typing:
   mumble-overlay gamename
-
-### Global Keyboard Events
-
-On Linux, Mumble supports reading the kernel input devices. To use this,
-make sure mumble can open `/dev/input/event*` for reading. To test it out,
-that should only require:
-
-```
-  sudo chmod a+r /dev/input/event*
-```
-
-However, be aware that this will most likely only last until the next reboot
-(at which point devfs is recreated) and you also allow any program run by any
-user to monitor the physical keyboard.
-
-Without this, Mumble will continuously poll the mouse and keyboard state for
-changes, which will use a tiny bit of processing power.
-

docs/GlobalShortcuts.md

@@ -0,0 +1,45 @@
+# Global shortcuts
+
+## Windows
+
+No additional steps should be required.
+
+If you're encountering problems, feel free to open an issue.
+
+## Linux
+
+### Poll-driven engine
+
+Uses a little more processing power, but no additional steps are required.
+
+### Event-driven engine
+
+Mumble needs read permissions for `/dev/input/event*`.
+
+The solution usually consists in adding your user to the `input` group:
+
+```
+sudo usermod -a -G input user
+```
+
+Please note that this allows any applications running under the same user
+to read data sent by input devices.
+
+If the solution doesn't work for you, you could allow all users to read the input:
+
+```
+  sudo chmod a+r /dev/input/event*
+```
+
+Please note that this is only meant to be a temporary solution, because:
+
+- It will most likely only last until the next reboot
+(at which point devfs is recreated).
+- It allows any applications to read the input data,
+regardless of the user they're running under!
+
+## macOS
+
+Mumble needs to be granted accessibility permissions.
+
+![macOS screenshot](../screenshots/macOS_privacy_accessibility.png)