According to the main developer's website this application has been discontinued. See https://arsenarsen.com/
KShare is a screenshotting utility built using Qt and written in C++. It has many features, including:
Area capture, Fullscreen capture, Active window capture, Magnifier, to make those aligments, Drawing on screenshots (blur, shapes, text, …), Recording, Highly customizable video codecs, Automatic upload/clipboard copying, Hotkeys, Color picker, and last but not least, Custom upload destinations It works on Linux, Windows, and Mac OS X, one program, one format, same functionality
The official is dead but someone picked it up here: https://github.com/Gurkengewuerz/KShare
Working.
Perfect full featured screenshot tool for Linux. Good alternative to sharex, even on Windows. (BTW this program is on Windows and MacOS)