dynamicBrandingUrl not being used / clients not accessing the URI?

Jitsi Version: 2.0.6433
not Docker or Debian packages, this is a self-install

When i configure the dynamicBrandingUrl to provide Virtual Backgrounds it seems to get ignored entirely. Is there another parameter required to be set for the dynamicBranding to work? Client/Browser doesnt even attempt to load the URL with the json, nor do i have errors in the developer console. I am not sure where/how to start finding the cause.

Is the dynamicBrandingUrl the proper tool to configure a site-wide config as well? Am I missing something obvious here? According to the docs at https://developer.8x8.com/jaas/docs/jaas-prefs-advanced-brandingit seems that all options are optional → only provided backgroundcolor and virtualbackgrounds for testing.

dynamicBrandingUrl: 'https://meet.domain.com/branding/test.json',

the json is provided at the URL is valid according to jq, it only contains:

{
   "backgroundColor":"#FFF",
   "virtualBackgrounds": ["https://meet.domain.com/branding/static/branding1.png"]
}

my entire config:

/* eslint-disable no-unused-vars, no-var */
var config = {
hosts: {
 domain: 'meet.domain.com',
 anonymousdomain: 'guest.meet.domain.com',
 muc: 'conference.meet.domain.com',
 focus: 'focus.meet.domain.com'
},
websocket: 'wss://meet.domain.com/xmpp-websocket',
bosh: 'https://meet.domain.com/http-bind',
websocketKeepAlive: '-1',
openBridgeChannel: 'websocket',
resolution: '2160',
constraints: {
 video: {
  frameRate: '30',
  height: {
   ideal: '2160',
   max: '2160',
   min: '180'
  },
  width: {
   ideal: '3840',
   max: '3840',
   min: '320'
  }
 }
},

dynamicBrandingUrl: 'https://meet.domain.com/branding/test.json',

disableSimulcast:false,
enableRemb:false,
enableTcc:true,
disableRtx:false,
useStunTurn:true,
p2p: {
 enabled:false,
 enableUnifiedOnChrome:true,
 useStunTurn:true,
 stunServers: [
  { urls: 'stun:stun.domain.com:443' }
 ],
},

testing: {
 octo: {
  probability:1.0
 }
},
channelLastN:15,
//lastNLimits: {
// 5: 20,
// 30: 15,
// 50: 10,
// 70: 5,
// 90: 2
//},

enableLayerSuspension:true,
useNewBandwidthAllocationStrategy:true,
enableForcedReload:true,
enableUnifiedOnChrome:true,
enableLipSync:false,
disableLocalVideoFlip:true,
disableAGC: false,
disableAEC: false,
disableNS: false,

videoQuality: {
 preferredCodec: 'VP9',
 enforcePreferredCodec: 'false',
 maxBitratesVideo: {
  low:200000,
  standard:500000,
  high:1500000,
  H264: {
   low:200000,
   standard:500000,
   high:1500000
  },
  VP8: {
   low:200000,
   standard:500000,
   high:1500000
  },
  VP9: {
   low:100000,
   standard:300000,
   high:1200000
  }
 },
 resizeDesktopForPresenter:true
},

startAudioMuted:10,
//startVideoMuted:10,
startAudioOnly:true,

enableWelcomePage:true,
prejoinPageEnabled:true,
defaultLanguage: 'de',
enableClosePage:true,
noticeMessage:null,
startBitrate:800,
disableAudioLevels:false,
audioLevelsInterval:200,
stereo:false,
enableNoisyMicDetection:false,
enableNoAudioDetection:true,
enableTalkWhileMuted:true,
forceJVB121Ratio:-1,
requireDisplayName:true,
disableJoinLeaveSounds:false,
enableInsecureRoomNameWarning:false,
disableDeepLinking:true,
transcribingEnabled:false,
liveStreamingEnabled:false,
enableScreenshotCapture:false,
fileRecordingsEnabled:false,
enableUserRolesBasedOnToken:false,
disableThirdPartyRequests: 'true',
MOBILE_APP_PROMO:false,
fileRecordingsServiceSharingEnabled:false,
fileRecordingsServiceEnabled:false,

enableReactions: true,
disablePolls: false,
disableShowMoreStats: false,
disableSpeakerStatsSearch: false,
disableIncomingMessageSound: false,


toolbarButtons:[
 'microphone',
 'camera',
 'closedcaptions',
 'desktop',
 'fullscreen',
 'fodeviceselection',
 'hangup',
 'profile',
 'info',
 'chat',
 'etherpad',
 'settings',
 'raisehand',
 'videoquality',
 'filmstrip',
 'invite',
 'stats',
 'shortcuts',
 'tileview',
 'select-background',
 'videobackgroundblur',
 'mute-everyone',
 'mute-video-everyone',
 'security',
 'participants-pane'
],

analytics: {
 disabled: true,
},

//dialOutAuthUrl:null,
//dialOutCodesUrl:null,
//dynamicBrandingUrl:null,

makeJsonParserHappy: 'even if last key had a trailing comma'

};