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

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

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]>>>.