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

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

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]>>>.