Soy_Magnus (npub1xe5…xg59) Rheristies (npub1lyr…pjx6) Zergling_man (npub140w…su0k)
Unless you are dealing with massive capacitors (>1F), if power has been removed for over a few minutes, you are probably fine. You can also short the terminals with a piece of wire (that you are electrically insulated from!!!) to force it to discharge, but this may involve sparks. Shoving the terminals into dirt probably will also work (dirt is somewhat conductive) and dirt is not likely to catch fire.
But when in doubt, let it sit for several days.