Flying glass panes are an obstacle encountered in Checkpoint 10, Checkpoint 11, and Zen Mode. The glass flies towards you, becoming a dangerous hazard, it jumps towards you in Checkpoint 10 stage 3. In Checkpoint 11, the glass might self-destruct. Zen Mode glass panes will always avoid you.
In Checkpoint 10 rooms 3 and 4 (and occasionally room 2 of checkpoint 11), pausing but then unpausing the game actually causes the panes to be triggered early, and in most cases miss you. However, this is a possibly dishonest use of the pause button.
A trick is to use one ball (preferably the quintuple-ball) to hit one, and knock everything else out of the way. (Only works in Low Gravity and does not typically work with single-ball)
That one glass panel that randomly flew across my screen
