Hi! If the subpage feature  is enabled for the Main (default) namespace we can get proper functioning of subpage links . This saves a lot of work and avoids broken links when pages are moved around, helps with creating documentation (see e.g. Kexi/Handbook). Also breadctumbs shall work eventually.
I propose the same for techbase and community wikis.
Seems like a good idea. Though it might need some testing. And also, techbase and communitybase are not yet updated like userbase, which might involve issues with the old codebase. About to happen though, soon.