I am fortunate enough to have a friend who bought two containers of waterproof matches, just for the containers (he was making geocaches), and he gave me all the matches.
But being the little firebug I am, I used most of them just playing around...I know, I know, I shouldn't have wasted those when I had all kinds of other matches, but then I had an epiphany.
There's a couple of 'ibles that show you how to make a little spice rack that you can take with you anywhere, by using drinking straws and melting/fusing the ends. If you can do it with salt, why not matches?
So that's what I did. And for the last hour or so, they've been sitting in this little container of water, so far, no bubbles.
And I'm fairly certain that even if I left them there for a year, they'd still light when freed from their plastic confines.
The method for these little 'blister packs' is very easy.
Take the straw, hold it by one end with pliers, and bring a lighter or match very close to it so that the end melts together. Insert match. Trim the straw, making sure to leave enough room at the end so that you can still grab it with pliers, and repeat the sealing process.
To open, cut with the scissors on your multi-tool, or using a sharp knife, and open just below your melted seal. Especially if it's something like a little packet of magnesium or something that you're not going to use all of, that way you can re-seal it.