I'm not sure if I'm just having a very large brainfart or substituting is legitimately bugged, which is why I'm reporting it here before going to support.
Essentially, I wanted to substitute all the page content from my fanfiction page Mutiny to my temporary text page (basically my sandbox for writing) so that I wouldn't have to go to the fanfic page and copypaste it. As you can see in the temporary text diff, I added {{subst:Mutiny}}, but it had no effect. Adding {{:Mutiny}} however does include the page's content properly. Weirdly enough, substituting worked a few weeks earlier from Temporary Text to Mutiny.
I tested this in a sandbox on a different wiki with the wiki's Cassowary page just to double check that it wasn't a weird wiki exclusive quirk, and again, it did not substitute. I tested substituting a template the next edit, and it did work.
Obviously, it's not a big loss if I have to copypaste Mutiny over to Temporary Text with ctrl a, but is this actually a bug or am I silly with substitution?
