[3.16]Wonders

when you finish a wonder, they don't display their characteristic in the pop-up.

That is correct, this is by design.

The mod changes so many details and the descriptions of them are automatically formulated to display inside the pedia or the techtree.

However the text that displays along with the Wonder splash doesn't fit with this standard and is made blank instead.

We figure you already know what the Wonder does, that is why you built it!

At any rate, if unsure the pedia still has the details.