When I created this block:
The remove slots arrow overlapped the triple ellipsis, and the border above and below a line (such as below the "do" section in this image is cut off for the "over" section making the number inputs look like they fell to the bottom of their area instead of being centered along with the text.
I'm pretty sure the ellipsis being on top of the arrow was a design decision (which is why I deliberately coded it into snapblocks @delInput @verticalEllipsis :: other ), however the inputs not being vertically aligned was most likely not intentional.
Really? It seems to me to be more like not having it be possible until v10 (that I know of), and not writing a case for it.