How do you freeze homemade stock?

I have 2 cup wide-mouth ball jars that I use. You can buy plastic lids that you can wash in the dishwasher along with the jars. (I also portion some into the smaller ball jars as well, but most soup recipes seem to call for at least 2 cups). Also, portioning out the stock into the jars while it's cooling helps it cool down a bit faster as well. I then just put in the fridge to cool and then later transfer to the freezer.

I freeze in batches in a silicone muffin tray and then store in plastic bags once they are frozen. I know that each "muffin" is about 1/2 c, so I can just defrost however many I need.

I freeze some in ice cube trays and some in repurposed quart yogurt containers. and some in glass quart jars. I always cool the quart containers in the fridge before freezing.

I always let it cool in the fridge overnight, even if like Susan I have to switch containers. Then I usually put it into freezer bags in one and two cup portions and freeze it flat. I've never had any issues with it leaking in the freezer, and then when it's time to thaw I just thaw it in a bowl so that if there are any leaks, I don't lose the stock and it doesn't make a mess. Sometimes I cut the plastic bag off while the block is still frozen, but either way it still goes in a bowl.

I strain my stock into a big stainless bowl. It doesn't take long to cool down in the fridge, but I let it semi-cool on my counter so I don't heat my fridge with hot stock. I let it sit overnight in the fridge and the next morning, I remove the fat. Then I usually portion it out into different size glass pyrex containers and/or mason type jars.

I freeze in air tight plastic quart containers with twist on lids. The way to cool down the stock faster is with an ice bath. Transfer the stock from the pot into smaller vessels that will fit inside a bowl filled with ice water. Stir periodically. It should cool down pretty fast and then you can transfer to containers for freezing.

Sometimes I freeze it in ice cube trays then keep the frozen cubes in a ziplock, but this isn't very practical for a big batch and usually I freeze cool/room temperature stock in quart bags like you. To defrost I run the bag under warm water for a few seconds, then I can slip the stock out of the bag into a bowl to defrost. I'm always a little nervous about leaking in the freezer too, but I've never had that problem.