I’ve just received a mail from Tumblr support, saying that the function Filter By Type depended on is “not supported at this time”, which is kinda open to interpretation. I’m pretty sure it means “removed forever”, though.

Unfortunately, without that function, Filter By Type can not work. Unless it makes a comeback, Filter By Type will be removed from the extension gallery soon, since right now, all it does is show an error window.

You can mail the Tumblr support (at support@tumblr.com) and ask them (politely, of course) to bring the “show pages” (ie: www.tumblr.com/show/audio) back, but not sure if that would make a change.

I’m deeply sorry about this, but it is beyond my control.