I feel like I should add for people struggling with this issue that this only affects manually placed jigsaws. Generated structures with jigsaws are not affected.
I am experiencing this as well. It also fails to find other jigsaw blocks some of the time. (1.19.2)
Matthgeek
I feel like I should add for people struggling with this issue that this only affects manually placed jigsaws. Generated structures with jigsaws are not affected.