After about 12 hours into fermentation my stopper popped out. I fixed the problem. My question is, it was off for about an hour, did this just destroy my batch? Thanks!
I wouldn't worry, you should be okay. Now, if your FV is located somewhere where exposure to contaminants is high or wild yeast could be present (outdoors), then you might have reason to be concerned.
After about 12 hours into fermentation my stopper popped out. I fixed the problem. My question is, it was off for about an hour, did this just destroy my batch? Thanks!
Most likely not, especially if it was actively fermenting as this will produce a positive internal pressure and a layer of C02, both of which will help prevent oxidation (which is probably not much of a concern at this point) and infection. Open fermentation is still practiced with much success, and no lids are used, let alone stoppers or airlocks.
I wouldn't worry too much about it unless you have a curious dog or children that may have been in the area during that time.