diff --git a/MediaBrowser.Providers/Plugins/Tmdb/Configuration/PluginConfiguration.cs b/MediaBrowser.Providers/Plugins/Tmdb/Configuration/PluginConfiguration.cs
index 0ebeebf1e2..b3a67189bb 100644
--- a/MediaBrowser.Providers/Plugins/Tmdb/Configuration/PluginConfiguration.cs
+++ b/MediaBrowser.Providers/Plugins/Tmdb/Configuration/PluginConfiguration.cs
@@ -58,12 +58,12 @@ namespace MediaBrowser.Providers.Plugins.Tmdb
 
         /// <summary>
         /// Gets or sets the ids (the "N" formatted GUIDs from <c>VirtualFolderInfo.ItemId</c>) of the
-        /// libraries for which the unaired/missing episode provider is disabled. Whether episodes are
-        /// imported at all, and how, is still controlled by the global toggles above; this list only
-        /// opts individual libraries out. Libraries not listed here are enabled, so the global toggles
-        /// apply to every library unless it is explicitly opted out.
+        /// libraries for which the unaired/missing episode provider is enabled. Whether episodes are
+        /// imported at all, and how, is still controlled by the global toggles above; those toggles only
+        /// apply to the libraries listed here. Libraries not listed, including newly added ones, are
+        /// never processed, so an empty list disables the feature entirely.
         /// </summary>
-        public string[] DisabledMissingEpisodeLibraries { get; set; } = [];
+        public string[] EnabledMissingEpisodeLibraries { get; set; } = [];
 
         /// <summary>
         /// Gets or sets how often, in days, the scheduled task re-checks TMDb for newly announced
diff --git a/MediaBrowser.Providers/Plugins/Tmdb/Configuration/config.html b/MediaBrowser.Providers/Plugins/Tmdb/Configuration/config.html
index b010749936..582753759f 100644
--- a/MediaBrowser.Providers/Plugins/Tmdb/Configuration/config.html
+++ b/MediaBrowser.Providers/Plugins/Tmdb/Configuration/config.html
@@ -56,7 +56,7 @@
                     </div>
                     <div class="verticalSection">
                         <h2>Libraries</h2>
-                        <div class="fieldDescription" style="margin-bottom:1em;">Choose which TV libraries the unaired/missing episode options above apply to. The settings above are global; this only controls which libraries they run for. New libraries are enabled by default.</div>
+                        <div class="fieldDescription" style="margin-bottom:1em;">Choose which TV libraries the unaired/missing episode options above apply to. The settings above are global; this only controls which libraries they run for. Libraries are opted in individually, so newly added libraries are not processed until they are enabled here.</div>
                         <div id="missingEpisodeLibraries"></div>
                     </div>
                     <div class="verticalSection">
@@ -119,7 +119,7 @@
                     Dashboard.showLoadingMsg();
 
                     var clientConfig, pluginConfig;
-                    var populateMissingEpisodeLibraries = function (disabledLibraries) {
+                    var populateMissingEpisodeLibraries = function (enabledLibraries) {
                         var container = document.querySelector('#missingEpisodeLibraries');
                         ApiClient.getVirtualFolders().then(function (folders) {
                             // Series only live in TV libraries (and mixed-content libraries, which report
@@ -134,7 +134,7 @@
                             }
 
                             container.innerHTML = tvLibraries.map(function (folder) {
-                                var checked = disabledLibraries.indexOf(folder.ItemId) === -1 ? ' checked' : '';
+                                var checked = enabledLibraries.indexOf(folder.ItemId) === -1 ? '' : ' checked';
                                 return '<label class="checkboxContainer">'
                                     + '<input is="emby-checkbox" type="checkbox" class="missingEpisodeLibrary" data-library-id="' + folder.ItemId + '"' + checked + ' />'
                                     + '<span>' + folder.Name + '</span>'
@@ -216,7 +216,7 @@
                         document.querySelector('#hideMissingCastMembers').checked = config.HideMissingCastMembers;
                         document.querySelector('#hideMissingCrewMembers').checked = config.HideMissingCrewMembers;
 
-                        populateMissingEpisodeLibraries(config.DisabledMissingEpisodeLibraries || []);
+                        populateMissingEpisodeLibraries(config.EnabledMissingEpisodeLibraries || []);
 
                         var maxCastMembers = document.querySelector('#maxCastMembers');
                         maxCastMembers.value = config.MaxCastMembers;
@@ -258,9 +258,12 @@
                         config.ImportSpecials = document.querySelector('#importSpecials').checked;
                         config.MissingEpisodeRefreshIntervalDays = parseInt(document.querySelector('#missingEpisodeRefreshIntervalDays').value, 10);
                         config.UpcomingEpisodeGracePeriodDays = parseInt(document.querySelector('#upcomingEpisodeGracePeriodDays').value, 10);
-                        config.DisabledMissingEpisodeLibraries = Array.prototype.map.call(
-                            document.querySelectorAll('.missingEpisodeLibrary:not(:checked)'),
-                            function (checkbox) { return checkbox.getAttribute('data-library-id'); });
+                        var libraryCheckboxes = document.querySelectorAll('.missingEpisodeLibrary');
+                        if (libraryCheckboxes.length > 0) {
+                            config.EnabledMissingEpisodeLibraries = Array.prototype.filter
+                                .call(libraryCheckboxes, function (checkbox) { return checkbox.checked; })
+                                .map(function (checkbox) { return checkbox.getAttribute('data-library-id'); });
+                        }
                         config.MaxCastMembers = document.querySelector('#maxCastMembers').value;
                         config.MaxCrewMembers = document.querySelector('#maxCrewMembers').value;
                         config.HideMissingCastMembers = document.querySelector('#hideMissingCastMembers').checked;
diff --git a/MediaBrowser.Providers/Plugins/Tmdb/TV/TmdbMissingEpisodeProvider.cs b/MediaBrowser.Providers/Plugins/Tmdb/TV/TmdbMissingEpisodeProvider.cs
index a0a5e8fdf8..b44361e4e7 100644
--- a/MediaBrowser.Providers/Plugins/Tmdb/TV/TmdbMissingEpisodeProvider.cs
+++ b/MediaBrowser.Providers/Plugins/Tmdb/TV/TmdbMissingEpisodeProvider.cs
@@ -75,8 +75,8 @@ namespace MediaBrowser.Providers.Plugins.Tmdb.TV
             var importMissing = (configuration?.ImportMissingEpisodes).GetValueOrDefault();
 
             // The provider is inactive for this series when both global imports are off, or the series'
-            // library has been opted out. In either case remove every virtual episode (unaired and missing
-            // alike) it previously created, so disabling the feature cleans up on the next library scan.
+            // library has not been opted in. In either case remove every virtual episode (unaired and
+            // missing alike) it previously created, so disabling the feature cleans up on the next scan.
             if ((!importUnaired && !importMissing) || !IsEnabledForLibrary(item))
             {
                 if (!PruneAllVirtualEpisodes(item))
@@ -352,22 +352,16 @@ namespace MediaBrowser.Providers.Plugins.Tmdb.TV
 
         private bool IsEnabledForLibrary(BaseItem item)
         {
-            var disabledLibraries = Plugin.Instance?.Configuration.DisabledMissingEpisodeLibraries;
-            if (disabledLibraries is null || disabledLibraries.Length == 0)
+            var enabledLibraries = Plugin.Instance?.Configuration.EnabledMissingEpisodeLibraries;
+            if (enabledLibraries is null || enabledLibraries.Length == 0)
             {
-                return true;
+                return false;
             }
 
-            // A series can live under more than one collection folder; treat it as disabled only when
-            // every containing library is opted out.
-            var collectionFolders = _libraryManager.GetCollectionFolders(item);
-            if (collectionFolders.Count == 0)
-            {
-                return true;
-            }
-
-            return collectionFolders.Any(folder =>
-                !disabledLibraries.Contains(folder.Id.ToString("N", CultureInfo.InvariantCulture), StringComparer.OrdinalIgnoreCase));
+            // A series can live under more than one collection folder; opting in any one of them is
+            // enough. An item that belongs to no collection folder cannot be opted in at all.
+            return _libraryManager.GetCollectionFolders(item).Any(folder =>
+                enabledLibraries.Contains(folder.Id.ToString("N", CultureInfo.InvariantCulture), StringComparer.OrdinalIgnoreCase));
         }
 
         private (HashSet<(int Season, int Episode)> Keys, Dictionary<(int Season, int Episode), Episode> Updatable) GetExistingEpisodes(Series series, bool pruneAgedOut, DateTime today, int gracePeriodDays, bool importSpecials, out bool pruned)
diff --git a/MediaBrowser.Providers/Plugins/Tmdb/TV/TmdbUpcomingEpisodesTask.cs b/MediaBrowser.Providers/Plugins/Tmdb/TV/TmdbUpcomingEpisodesTask.cs
index bb8c9bdcf2..e2846c74a3 100644
--- a/MediaBrowser.Providers/Plugins/Tmdb/TV/TmdbUpcomingEpisodesTask.cs
+++ b/MediaBrowser.Providers/Plugins/Tmdb/TV/TmdbUpcomingEpisodesTask.cs
@@ -85,14 +85,15 @@ namespace MediaBrowser.Providers.Plugins.Tmdb.TV
 
             // The feature is fully disabled: remove every virtual episode (and now-empty virtual season)
             // this provider previously created, across all libraries, then stop.
-            if (!configuration.ImportUnairedEpisodes && !configuration.ImportMissingEpisodes)
+            if ((!configuration.ImportUnairedEpisodes && !configuration.ImportMissingEpisodes)
+                || configuration.EnabledMissingEpisodeLibraries.Length == 0)
             {
                 RemoveAllVirtualItems(progress, cancellationToken);
                 return;
             }
 
             // Process non-ended series (they may have gained episodes) plus any series in a library that
-            // has been opted out (regardless of status) so the provider can prune the virtual episodes it
+            // is not opted in (regardless of status) so the provider can prune the virtual episodes it
             // previously created there. Ended series in enabled libraries cannot change, so they're skipped.
             var series = _libraryManager.GetItemList(new InternalItemsQuery
             {
@@ -142,22 +143,16 @@ namespace MediaBrowser.Providers.Plugins.Tmdb.TV
 
         private bool IsEnabledForLibrary(BaseItem item)
         {
-            var disabledLibraries = Plugin.Instance?.Configuration.DisabledMissingEpisodeLibraries;
-            if (disabledLibraries is null || disabledLibraries.Length == 0)
+            var enabledLibraries = Plugin.Instance?.Configuration.EnabledMissingEpisodeLibraries;
+            if (enabledLibraries is null || enabledLibraries.Length == 0)
             {
-                return true;
+                return false;
             }
 
-            // A series can live under more than one collection folder; treat it as disabled only when
-            // every containing library is opted out.
-            var collectionFolders = _libraryManager.GetCollectionFolders(item);
-            if (collectionFolders.Count == 0)
-            {
-                return true;
-            }
-
-            return collectionFolders.Any(folder =>
-                !disabledLibraries.Contains(folder.Id.ToString("N", CultureInfo.InvariantCulture), StringComparer.OrdinalIgnoreCase));
+            // A series can live under more than one collection folder; opting in any one of them is
+            // enough. An item that belongs to no collection folder cannot be opted in at all.
+            return _libraryManager.GetCollectionFolders(item).Any(folder =>
+                enabledLibraries.Contains(folder.Id.ToString("N", CultureInfo.InvariantCulture), StringComparer.OrdinalIgnoreCase));
         }
 
         /// <summary>