Why did the fill valve in my toilet pop up?

The fill valve in one of my toilets popped up with enough force that it lifted the toilet cover up and nearly off the toilet. Anyone heard of this happening, and any ideas what might have caused it? I pushed it down and it clicked, and now everything works again (see picture).

My best and only guess is that it has something to do with in-tank toilet cleaner thing that was in there (we moved in recently, I didn’t know it was there). Maybe it was floating around free and got caught on something? I’m not sure, this all happened when I wasn’t in the room.

Bottom line is I’m probably going to replace the fill valve, I’m just wondering if anyone has any insight into what might have happened.