It's in Debian (possibly upstream only), but you can download the latest version from their website and install it manually.
The MX 15/ MEPIS repositories
: Backports galore! If we don't have something, just ask and we'll try--we like challenges. New packages: plank 0.11.1, Pale Moon 26.2.2, Liquorix kernel 4.6-3, mpv 0.17, Kodi 16.1, QBittorrent 3.3.5, SMPlayer 16.6.0