Unity. Doesn't work minimizing single foreground window by clicking on it's icon on Unity's launcher

Clicking a running application's icon in the launcher brings all its windows to the foreground. That essential functionality would be gone if clicking the icon had the opposite effect of minimizing all the application's windows. Therefore, it does not appear that the change you are recommending would be prudent. Can you present any evidence to show that a significant number of users (or even *any* other users) want this behavior?

Perhaps it would be better for the functionality of hiding all of an application's windows to be implemented in some other way, besides by clicking on its icon in the launcher. You might want to search to see if anyone has filed a bug here, or posted at http://brainstorm.ubuntu.com, to request this.

"Can you present any evidence to show that a significant number of users (or even *any* other users) want this behavior?"
I try, I think many of the Russian community of Ubuntu will support me.

"Clicking a running application's icon in the launcher brings all its windows to the foreground."
Apparently I did not put it quite clearly.

If you open multiple windows of one application and clicking a that application's icon in the launcher brings all its windows to the foreground - it is OK!
But if you run only one application window, after clicking a that application's icon nothing happens! And it will be perfect if that window will minimize by left mouse clicking! That's what I mean.

"I try, I think many of the Russian community of Ubuntu will support me."

If other users will subscribe to this bug and use the "This bug affects..." link near the top of the bug to indicate that this affects them (which, for feature requests like this, is taken to mean that they want the requested feature to be implemented), then it is possible that developers and the community at large will take notice. (Others should also feel free to post their thoughts here as comments if they wish, while also using the "This bug affects..." link.)

However...

"But if you run only one application window, after clicking a that application's icon nothing happens!"

That is not the case. Something does happen: that single application window is brought to the foreground (made to be in front of other windows for other applications, and made to be the active window, so that, for example, it is the window to which typed text is sent). The only situation where nothing happens is if it is already the foreground window. But if it is already the foreground window, then isn't it trivially easy simply to click its minimize button (since the minimize button is necessarily visible)?

Remember, being minimized and being the foreground window are not the only two possibilities, and when many applications are run at at time, often most windows will be in neither of these two states.

"The only situation where nothing happens is if it is already the foreground window."
Exactly!

If you add the ability to minimize such windows by clicking on the icon - it would be very easy to switch between applications (unless they are deployed on the entire screen)!

The mouse pointer can easily and quickly accessible by the application icon than by minimize button!

On the one hand, it might be considered undesirable to introduce inconsistency by making clicking on a running application's icon in the launcher minimize the application, in just this one particular case. But on the other hand, this would arguably not really be inconsistency. When an application is in the foreground but has multiple windows and you click its icon in the launcher, all the windows are shrunk down and displayed so you can select between them. When there is only one window, it might make sense for it to "shrink down" to nothingness and give way to other applications' windows, as this feature request argues should happen.

It seems to me that there remains a very serious problem with this proposal, however: When a user clicks an application's icon in the launcher, it is typically with the intention of causing all the application's windows to be displayed. Often, an application might have only one window, but the user might not be sure of that. Clicking a foreground application's icon in the launcher is currently an excellent way to find out if there are other windows associated with that same application. With the change proposed here, the user would have to click it (finding out it's the only one, because it the window disappears), and then click it again to make the window reappear. Right now, when an application has a foreground window, clicking the application's icon in the launcher is the only efficient way to determine if it has other windows. With the proposed change, would there be any efficient way for a user to determine if the foreground window is the only window in its application?

Of cause, you have described this!
"Clicking a foreground application's icon in the launcher is currently an excellent way to find out if there are other windows associated with that same application. With the change proposed here, the user would have to click it (finding out it's the only one, because it the window disappears), and then click it again to make the window reappear."