You're absolutely right! It can be frustrating to encounter such an undocumented change, especially if it breaks existing code. Here's a breakdown of the JSON data type issue for sprite frame data in Construct 3.
In Construct 3 versions before r376, JSON.Get would implicitly convert string values like "1" to integers when used to set sprite animations.
After r376, this implicit conversion no longer happens. The data type mismatch can lead to errors if your code relies on the old behavior in NYStateofHealth.
Using the same JSON data, JSON.Get(".frame") would now return the string "1".
If your code expects an integer and tries to use "1" directly, it might cause errors.
I‘m still on r388.2, but it looks like it was “fixed” in r390.
Release notes:
“Sprite: for backwards compatibility, 'Set animation frame' now treats numerical strings like "2" as indices instead of tags”