Very cool game. It would be great if you could make the timer pause if I take off browser focus (say, to check a different tab on something unrelated while playing).
EDIT: It would also be helpful if all the mines were revealed upon losing for educational purposes.
EDIT #2: It would be awesome if we could control map size. Maybe Triangulation could be continually procedurally generated and even be made into an endless MMO! For example, here is an infinite Minesweeper MMO: https://mienfield.com