4 Environment. Currently Debian GNU/Linux 10 (Buster).
13 - `ls` and `tree` (primary)
14 - `pcmanfm` (secondary)
15 - `ranger` (occasional)
33 - `ncmpc` (to delete from playlist, which doesn't work in `ncmpcpp`)
35 - [soma fm](http://somafm.com/) (primary) (via `mpd`)
36 - `spotify` (occasional)
57 - `qutebrowser` (primary)
58 - `chromium` (fallback)
59 - `elinks` (occasional)
60 - `ddgr` (occasional small web search)
63 - `khatus` (currently x2)
68 - `hsetroot` (background color)
69 - `feh` (background image)
75 - [doodle](https://grothoff.org/christian/doodle/)