DBM or BigWigs not working in WoW Forever: no timers, missing dungeons

If DBM or BigWigs shows no timers in a WoW Forever dungeon, the usual cause is a missing dungeon add-on: both keep dungeon bosses outside their core download. Both cores have Forever builds. What differs is the dungeon data.

DBM: install DBM-Dungeons

Deadly Boss Mods (DBM) needs DBM-Dungeons for five-player content. That add-on has a DBM-Party-Forever module with Forever's dungeons, and it was still being updated on 2 November.

BigWigs: dungeons are the catch

BigWigs Bossmods keeps dungeons in LittleWigs. When we checked on 2 November, LittleWigs' file list had no Forever version number and no Forever folder. So in dungeons, expect BigWigs to show little or nothing until that changes. For now, DBM has the better dungeon coverage.

Raids

Forever's raids open on 9 December, so raid modules for them can't be tested on live yet. Update on raid day.

Other checks

Update both the add-on and its modules. New content changes quickly.
Run one boss mod. Two means duplicate warnings and more to go wrong.
Test the bars. /dbm or /bw opens the options, which have a test button. If test bars show but real ones don't, the module for that boss is missing.
Sound missing in DBM: its changelog mentions fixing an error when your language's default voice pack isn't installed, so update first.
Lua errors: install BugSack and report the first line to the add-on's tracker, saying you play WoW Forever.

A limit nobody can fix

Blizzard named boss timers among the things it's building natively, and it restricts what add-ons can read in combat (Blizzard's post, written for Midnight). Forever appears to share those rules, so boss mods may show less than players remember from Classic. We'll report what we see on live.

Choosing between them: DBM vs BigWigs.