Given a character matrix, your task is to identify the positions of all squares with a length of at least 3 and output the row and column numbers of the bottom-right corner of these squares. The squares are composed of the same character, and each side has a length of at least 3.

If the matrix is

T X A L J V X Y Y L R U X I
E G D U Y T C F F F F L I U
K X S B E R D F F F F U S R
F G U K P F O F F F F F C E
C K W Z C V Y F F F F F K D
H E N J Y T O V M U O Y J J
R A Y Y N K K I K I O P D P
E M G B E E G X G P T R K K

Please provide the row and column of the bottom-right vertex of the square in the character matrix with a side length of at least 3 (the answer is unique). Notice: All coordinates start from 0.  

Your answer should be in the format <<<[row, column]>>>.