For MIUI loyal users, in the Nightly version, the newly added internal testing function should arouse your interest. Specifically, the screenshot of the area in MIUI 12 20.5.25 can be called by long-pressing the Home button 
There are other activation methods expected), and then the screenshot toolbar will pop up in the upper right corner, which is divided into three options: free shape, rectangle, and circle.
After capturing, the zoom buttons are also provided in the four corners of the screenshot to adjust the size at will.
After the screenshot is completed, below are the rotate, share, edit, and save option buttons. MIUI 12 new function exposure: can take screenshots of any shaped area
From the functional design level, it is more comprehensive, depending on Xiaomi’s decision when to package and push it to the stable version. At present, MIUI 12 has arrived in many models, the Redmi 10X just released will soon be upgraded.