In the top left corner of most editing windows is a button with a chain-link icon. This is called the Link button, and activating it links Logic's editing windows together. There are two ways to link windows together; the first is called Link mode, and the second is called Content Link mode.
In Link mode, the Link button is violet. With the Link mode enabled, all newly opened objects always open into the linked window.
In Content Link mode, the Link button is yellow, and the editors show the contents of any object selected in the active window.
These may seem like esoteric features at first glance, but they are very useful. The best way to see the differences between these two modes is to try them out.
Position the floating Matrix Editor so you can clearly see it and the Regions in the Arrange window.
In the Matrix Editor, click the Link button to turn it off (gray).
In the Arrange window, double-click the House Launch Pad MIDI Region.
The Region opens in a second Matrix Editor under the floating Matrix Editor that displays the Inst 2 MIDI Region. Because the Link buttons are not activated each time you open a new Matrix Editor, the editor opens in its own window. This is great if you need to work on the MIDI events of two or more MIDI Regions at the same time, but all these open Matrix Editors can quickly fill your screen. Let's see how linking windows solves this problem.
Close the Matrix Editor that just opened.
In the floating Matrix Editor, click the Link button once to turn it purple.
In the Arrange window, once again double-click the House Launch Pad MIDI Region.
This time, the MIDI Region opens in the floating Matrix Editor, replacing the events it previously displayed! With the Link button on, any time you open a Region into a Matrix Editor, it will always open in the linked Matrix Editor.
The Content Link mode works in a similar fashion, except you only have to select the MIDI Region in the Arrange window. Logic then prints the content of the selected Region into the content-linked window.
In the floating Matrix Editor, double-click the Link button.
The Link button turns yellow.
In the Arrange window, single-click the Inst 2 MIDI Region to select it.
The Region's eventsor rather, the content of the Regionappears in the floating Matrix Editor.
Close the floating Matrix Editor.