I would like to suggest that the quests json file save all variables set for a quest, even if they're default. Yes, it would make the file a tad bigger, but would prevent the following:

I realized that I need to change a bunch of quests (150+) from normal visibility to unlocked visibility because they're showing up when they shouldn't and causing a lot of brokenness. Instead of this being a simple 5 second replace task in n++ I now have to spend a lot of time in the designer going through every single quest to change this.

Build 3.5.296 is now up on Curse Forge. Should generate populate all the default visibility values for you.

It already should be saved to the file. I've never intentionally excluded default variables.

In that case it isn't. I searched for '"visibility:8"' before and after going through everything and it went from 21 or so to 160+. Here's a screenshot of before (left from my prior pack update) and right (after I went through everything), notice before doesn't have a visibility tag.

The other defaults appear to be there except that one. I think I might know where that issue is so I'll take a look at that today.

In the mean time you could try doing a find-and-replace on another default tag and append the visibility tag after it (would leave duplicates on the one's you've already done though)

I thought about that initially, but decided I didn't want to risk breaking something so I did it manually. It also forced me to comb over everything, which was helpful.