You have ten seconds to look at and rearrange the cards in your library. At the end of those ten seconds, if you're touching one or more of those cards, shuffle.
Hot Fix has 2 printings, first in Unstable (2017). It has 3 official rulings.
Legality
commander: not legal
legacy: not legal
vintage: not legal
pauper: not legal
modern: not legal
pioneer: not legal
standard: not legal
brawl: not legal
Rulings
: You can’t change the contents of the library.
: At the end of the ten seconds, your library must again be a single face-down pile of cards. If it’s not, you must shuffle your library, even if you weren’t touching it when time expired.
: Have another player keep time and announce when the ten seconds are up. If you’re still touching any cards in your library when time is up, you have to shuffle your library, undoing your ordering.