This is an icon with letters, which highlights the letter "o" on a red background. As a symbol representing O-type blood, it is common in medical and health organizations or institutions. In addition, this icon sometimes appears on some switch buttons, which means "open".
Different platforms depict different icons. Except LG platform displays black letters, other platforms use white letters. As for the shape of the letter "o", some seem to be round, similar to round; Others are oval, similar to the Arabic numeral "0".
