For comparison, GNOME has long had an app named Devhelp for reading API documentation with a sidebar allowing easy access to any installed docs that have registered themselves with a .devhelp2 file. GNOME has recently archived the Devhelp app in favor of a new app named Manuals which still supports the .devhelp2 files. (This app is currently in Debian's NEW queue.)
I count about 366 .devhelp2 files on my system. It is heavily weighted towards library used by app or system developers for GTK desktops (GNOME, Xfce, etc.). There are a few packages that provide the older .devhelp or .devhelp.gz format but Manuals does not support that format. I count about 4757 files in /usr/share/doc-base/ The devhelp app has a popcon of 1426 installs, larger than all the doc-base clients combined. The gnome-builder app has a popcon of 680 and gnome-builder has integrated devhelp2 support similar to the Manuals app. The .devhelp2 files are part of the upstream projects. I don't think anyone is writing those files downstream specifically for Debian. I'm not really suggesting now that devhelp be mentioned in Debian Policy, but this is just a contrast with an alternate way of solving this problem. Thank you, Jeremy Bícha
