How does Win10 pin any folder to the taskbar?

In Win10, when we want to "recycle the bin" or a folder we created ourselves, by dragging it to the taskbar, we often see the following situation. Don't we really have a way to pin any folder to the taskbar? The answer is of course no, let's take a look at the method below.

1. In the "Recycle Bin" or any other folder, here we have created a name called “ fixed to the taskbar! ” folder. Right click and select “fix to “start"screen";

2, then click the start button, you can see that our folder has been added Go to the start screen on the right. Then right click on it again, select “pin to the taskbar 

3, then come back and see if it is not possible to pin the folder to the taskbar. Has it been fixed on it?

4, but at this time, there are still folders we just added in the start screen. Let's delete it, click the Start button again, find the folder just right, then right click on it and select “From “Start”Screen Unpin “. Ok, the start screen doesn't show up, but it's still fixed on the taskbar! (The actual effect refers to the second picture)