I feel like this should be easy, so bear with me please.
On all manner of Special: pages, like Special:All Pages, you get to decide in which namespace to look, like so:
However, most of the default namespaces are either empty or irrelevant to every user except myself (it is a very small personal wiki that will never have more than one admin). Is there a way to hide all the "useless" namespaces from this dropdown and only keep the ones relevant to my users?
If not, is it possible to at least change the sort order of that dropdown? Currently, to get to the custom namespaces (which is what all my users want to do), you have to open the dropdown, then scroll it all the way to the bottom.