The public_url setting doesn't match the application url

[truthsword]

Running Docker on an RPi.

No apparent sync. The DB file size is unchanged (61440) from fresh start.

Docker compose...

version: "3.2"
services:
  firefox-syncserver:
    image: crazymax/firefox-syncserver:latest
    container_name: firefox_syncserver
    ports:
      - 5000:5000
    environment:
      - PUID=1000
      - PGID=1000
      - FF_SYNCSERVER_PUBLIC_URL='http://192.168.1.10:5000'
      - FF_SYNCSERVER_SECRET='somerandomstufftypedhere'
      - TZ=America/Chicago
    volumes:
      - /home/david/docker/ffsync/data:/data
    restart: always

I'm using http://192.168.1.10:5000/token/1.0/sync/1.5/ in the identity.sync.tokenserver.uri section of about:config. I tried this with and without the trailing slash after 1.5.

I must be missing something obvious. It can't be this hard... can it? Thanks!