Moving armor to armor slots while holding shift

[bugbug11]

While holding shift, clicking on the armor twice is required to move armor to armor slots. This isn't really a big problem, but it's something to be aware of.

[SmallJoker]

Interestingly this occurs with the unified_inventory mod but not with sfinv (from Minetest Game). The listring[] tags are identical, thus there must be some strange formspec update going on that confuses the client.