fix: append fragment cues when track mode is disabled

Author: eowino

index.d.ts

@@ -1732,6 +1732,7 @@ declare namespace dashjs {
                 scheduleWhilePaused?: boolean
             },
             text?: {
+                appendFragmentedCuesWhenTrackModeDisabled?: boolean,
                 defaultEnabled?: boolean,
                 dispatchForManualRendering?: boolean,
                 extendSegmentedCues?: boolean,

src/core/Settings.js

@@ -599,6 +599,9 @@ import Events from './events/Events.js';
 
 /**
  * @typedef {Object} Text
+ * @property {boolean} [appendFragmentedCuesWhenTrackModeDisabled=true]
+ * Whether fragment cues should be appended to the TextTrack when the track mode is set to disabled.
+ * Fragment cues are fetched once. This ensures we don't miss them when the track mode is set to disabled.
  * @property {boolean} [defaultEnabled=true]
  * Enable/disable subtitle rendering by default.
  * @property {boolean} [dispatchForManualRendering=false]
@@ -1203,6 +1206,7 @@ function Settings() {
                 scheduleWhilePaused: true
             },
             text: {
+                appendFragmentedCuesWhenTrackModeDisabled: true,
                 defaultEnabled: true,
                 dispatchForManualRendering: false,
                 extendSegmentedCues: true,

src/streaming/text/TextTracks.js

@@ -549,7 +549,12 @@ function TextTracks(config) {
                                     }
                                 }
                             } else {
-                                if (track.mode !== Constants.TEXT_DISABLED) {
+                                const isFragmented = this.getCurrentTrackInfo()?.isFragmented;
+                                const appendFragmentedCuesWhenTrackModeDisabled = settings.get().streaming.text.appendFragmentedCuesWhenTrackModeDisabled;
+
+                                // If disabled, add fragment cues as they'll be downloaded once.
+                                // If you miss them, they won't be downloaded again.
+                                if (track.mode !== Constants.TEXT_DISABLED || (appendFragmentedCuesWhenTrackModeDisabled && isFragmented)) {
                                     track.addCue(cue);
                                 }
                             }