Check Box with Check
A checkbox showing a check mark inside the box. Not to be confused with the similarly named Ballot Box With Ballot emoji, though Samsung did originally include a ballot box as part of this emoji's design.
This emoji is not supported in Twitter names, possibly in an attempt to minimize confusion with a verified checkmark.
Check Box with Check was approved as part of Unicode 1.1 in 1993 under the name "Ballot Box with Check" and added to Emoji 1.0 in 2015.