Trackbar for working with dates

Much has already been written on the topic of trackbars, but in the comments to past habratopics, someone was interested in a trackbar with two “sliders” so that the whole range could be shifted at once (rather than each sliders separately), and of course, each slider separately, naturally and written originally for working with dates). I piously swore to find such a notable thing, for I saw it the other day, and just now I came across it again.
Let me introduce you - The sliding date-picker .


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