A decade that cannot fill a mix no longer takes a weekly rotation slot.
Decades were ranked by plays alone, so a decade you play hard but own little of (a few 1970s singles on repeat) could win one of the two weekly decade slots and then come out under the 10 track minimum, where the plugin leaves it unwritten. That week showed one decade playlist instead of two, and nothing said why.
Decades now get the same floor Artist Radio and Genre Radio already have: only a decade with at least 10 tracks a mix can take under the per-artist cap is ranked. The ranking among eligible decades is unchanged.
Install: download navibeat-mixes.ndp below and upload it on the Navidrome Plugins page, replacing 0.9.10.