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The biggest problem with OS X that bothers me a lot is that when you are working with multiple applications and trying to switch between applications with mouse: first you have to click on the application and then start using it.
As an example, let's say we have two text editors that we are typing in each of them separately. Now lets say we want to copy a piece of text from first window to the second one. Based on OS X's behavioral semantics, you have to select the first window with a mouse click and then again press the mouse click to select a piece of text. This sometimes brings down my productivity by a lot in different applications.
In Microsoft Windows applications, there is no such concept. For the same scenario, if you click on some text on the a un-selected window, it will instantly start selecting the text without the need for selecting the application first. This is only one simple example.
The question is, is there anyway to enable a feature like this in OS X?