The way that editors are only active while the mouse is inside them can be problematic for the text editor. For that editor the mouse can get in the way so you might move it right out of the space and suddenly you don't know why your keys no longer work.
This patch makes the active caret position, selection areas, and line highlight all dim when the editor loses focus when you move the mouse out of it.
The top of the following image shows what it looks like when the mouse is positioned inside the Text editor area. To the right is what it looks like when you move your mouse outside of the area: