Me too, repeatedly. I've asked questions, reported bugs, asked for enhancements, made suggestions, submitted patches for consideration, and was always welcomed. Even when I'm asking for stuff that doesn't necessarily align with their goals.

OTOH, I've requested clarification (just some basic documentation really) on the “open contribution” fork of SQLite… and they never documented their own code.

And I'm sorry, I know sarcasm isn't the way here, and is impolite, but that was exactly the point.

Less than a week ago we had a whole thread where, again, we discussed the impossibility of improving SQLite from the outside because it's not “open contribution.”

Well, this is just a great example of much larger feature that was developed in collaboration with them.