Unable to propose a merge outside mainspace

[NovemLinguae]

Reported by Sdkb at https://en.wikipedia.org/wiki/Wikipedia_talk:Twinkle#Merging_help%2Fproject_pages

It looks like there's currently no way to nominate pages in the Help or Wikipedia namespaces for merging, because the merge function is under the tag menu, which appears only for articles. That's unfortunate, given that there are plenty of projectspace pages that could use merging, so we want to make it easy to suggest doing so. --Sdkb

One fix would be to move merge stuff from the Tag module into the XFD module, where things like AFD and RM are located.

[sdkb]

Thanks for creating the ticket!

I like the idea of moving to the XfD module, as merging seems more akin to the other stuff there (all of which is in the "affects the page structure of the encyclopedia" bucket) than it does to maintenance tags, even if it's not technically an XfD.

Before we go ahead with that, it is probably worth checking to see if anything else in the tag menu is applicable outside mainspace, since if so we'll have different considerations.

[Gonzom]

@sdkb , yes #1916 .