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

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

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]>>>.