diff --git a/src/csui/PlayerUiBase.vue b/src/csui/PlayerUiBase.vue
index 517f73e..306d802 100644
--- a/src/csui/PlayerUiBase.vue
+++ b/src/csui/PlayerUiBase.vue
@@ -86,6 +86,9 @@
             ></VideoSettings>
             <PlayerDetectionPanel
               v-if="selectedTab === 'playerDetection'"
+              :settings="settings"
+              :eventBus="eventBus"
+              :site="site"
             >
             </PlayerDetectionPanel>
             <!-- <ResizerDebugPanel :debugData="debugData">
@@ -188,6 +191,8 @@ export default {
   },
 
   async created() {
+    console.log('player-tree: player UI base created')
+
     this.logger = new Logger();
     await this.logger.init({
         allowLogging: true,
@@ -291,7 +296,7 @@ export default {
 
     selectTab(tab) {
       console.log('selected tab:', tab);
-      console.warn('NOTE: tab selection is not syet inplemented!')
+      console.warn('NOTE: tab selection is not syet inplemented!');
       this.selectedTab = tab;
     }
   }
diff --git a/src/csui/src/PlayerUiPanels/PlayerDetectionPanel.vue b/src/csui/src/PlayerUiPanels/PlayerDetectionPanel.vue
index b854a36..eb4d886 100644
--- a/src/csui/src/PlayerUiPanels/PlayerDetectionPanel.vue
+++ b/src/csui/src/PlayerUiPanels/PlayerDetectionPanel.vue
@@ -16,6 +16,19 @@
             You're probably on this page because Ultrawidify doesn't crop the player correctly. If you want to know more about
             why this happens, explanation can be found on <a href="https://github.com/tamius-han/ultrawidify/wiki/2.-Player-detection-(and-related-problems)#why-does-ultrawidify-have-this-problem-when-this-other-extension-doesnt" target="_blank">the wiki page</a>.
           </p>
+          <p>
+            If you hover over the boxes below, the corresponding element will change (sepia filter + higher brightness + reduced contrast + it gets an outline). Player element
+            should be the closest element to the video element, for which the sepia/brightness effect covers the area you expect the video will cover.
+          </p>
+
+          <div>
+            <b>Symbols:</b><br />
+            <mdicon name="alert-remove" class="invalid" /> Element of invalid dimensions<br />
+            <mdicon name="refresh-auto" class="auto-match" /> Ultrawidify's player detection thinks this should be the player<br />
+            <mdicon name="bookmark" class="parent-offset-match" /> Site settings say this should be the player (based on counting parents)<br />
+            <mdicon name="crosshairs" class="qs-match" /> Site settings say this should be the player (based on query selectors)<br />
+            <mdicon name="check-circle" class="activePlayer" /> Element that is actually the player
+          </div>
 
           <div class="element-tree">
             <div class="html-element-boxes">
@@ -25,19 +38,52 @@
                 class="element-row"
               >
                 <div class="status">
+                  <div
+                    v-if="element.heuristics?.invalidSize"
+                    class="invalid"
+                  >
+                    <mdicon name="alert-remove" />
+                  </div>
+                  <div
+                    v-if="element.heuristics?.autoMatch"
+                    class="auto-match"
+                  >
+                     <mdicon name="refresh-auto" />
+                  </div>
+                  <div
+                    v-if="element.heuristics?.qsMatch"
+                    class="qs-match"
+                  >
+                     <mdicon name="crosshairs" />
+                  </div>
+                  <div
+                    v-if="element.heuristics?.manualElementByParentIndex"
+                    class="parent-offset-match"
+                  >
+                     <mdicon name="bookmark" />
+                  </div>
+                  <div
+                    v-if="element.heuristics?.activePlayer"
+                    class="activePlayer"
+                  >
+                     <mdicon name="check-circle" />
+                  </div>
+
                 </div>
-                <div class="element-data">
+                <div
+                  class="element-data"
+
+                  @mouseover="markElement(index, true)"
+                  @mouseleave="markElement(index, false)"
+                >
                   <div class="tag">
-                    {{element.tagName}}
+                    <b>{{element.tagName}}</b> <i class="id">{{element.id ? `#`:''}}{{element.id}}</i>  @ <span class="dimensions">{{element.width}}</span>x<span class="dimensions">{{element.height}}</span>
+
                   </div>
-                  <div v-if="element.id" class="id">
-                    {{element.id}}
-                  </div>
-                  <div v-if="element.classList" id="class-list">
-                    {{element.classList}}
-                  </div>
-                  <div class="dimensions">
-                    {{element.width}} x {{element.height}}
+                  <div v-if="element.classList" class="class-list">
+                    <div v-for="cls of element.classList" :key="cls">
+                      {{cls}}
+                    </div>
                   </div>
                 </div>
                 <div class="css-fixes">
@@ -75,17 +121,78 @@ export default({
     'site'
   ],
   created() {
-    this.eventBus.subscribe('uw-player-tree', {function: (elementStack) => this.handleElementStack(elementStack)});
+    this.eventBus.subscribe('uw-config-broadcast', {function: (config) => this.handleElementStack(config)});
   },
   mounted() {
     this.eventBus.sendToTunnel('get-player-tree');  // TODO: implement this in PlayerData
   },
   computed: {},
   methods: {
-    handleElementStack(elementStack) {
-      this.elementStack = elementStack;
-      this.$nextTick( () => this.$forceUpdate() );
+    handleElementStack(configBroadcast) {
+      if (configBroadcast.type === 'player-tree') {
+        this.elementStack = configBroadcast.config;
+        this.$nextTick( () => this.$forceUpdate() );
+      }
+    },
+    markElement(parentIndex, enable) {
+      console.log('will mark element:', parentIndex, enable);
+      this.eventBus.sendToTunnel('set-mark-element', {parentIndex, enable});
     }
   }
 })
 </script>
+
+<style lang="scss" scoped>
+.element-tree {
+  .html-element-boxes {
+    display: flex;
+    flex-direction: column;
+
+    .element-row {
+      display: flex;
+      flex-direction: row;
+      margin: 0.5rem;
+
+      .status {
+        width: 6.9rem;
+        margin-right: 1rem;
+        display: flex;
+        flex-direction: row;
+        justify-content: flex-end;
+        align-items: center;
+
+        .invalid {
+          color: #f00;
+        }
+      }
+      .element-data {
+        border: 1px solid rgba(255,255,255,0.5);
+        padding: 0.5rem 1rem;
+
+        display: flex;
+        flex-direction: column;
+
+        .tag {
+          text-transform: lowercase;
+          font-weight: bold;
+        }
+        .id {
+          font-style: italic;
+        }
+        .class-list {
+          font-style: italic;
+          opacity: 0.75;
+          font-size: 0.75rem;
+
+          display: flex;
+          flex-direction: row;
+          flex-wrap: wrap;
+        }
+        .dimensions {
+          color: #473c85;
+        }
+      }
+    }
+  }
+}
+</style>
diff --git a/src/ext/lib/video-data/PlayerData.ts b/src/ext/lib/video-data/PlayerData.ts
index aa95c32..51054a0 100644
--- a/src/ext/lib/video-data/PlayerData.ts
+++ b/src/ext/lib/video-data/PlayerData.ts
@@ -96,6 +96,9 @@ class PlayerData {
       this.invalid = false;
       this.element = this.getPlayer();
 
+      this.eventBus.subscribe('get-player-tree', {function: () => this.handlePlayerTreeRequest()});
+      this.eventBus.subscribe('set-mark-element', {function: (data) => this.markElement(data)});
+
       // this.notificationService = new PlayerNotificationUi(this.element, this.settings, this.eventBus);
       this.ui = new UI('ultrawidifyUi', {parentElement: this.element, eventBus: this.eventBus});
       // this.ui.init();
@@ -413,6 +416,10 @@ class PlayerData {
     }
     return false;
   }
+
+  equalish(a,b, tolerance) {
+    return a > b - tolerance && a < b + tolerance;
+  }
   //#endregion
 
   /**
@@ -427,7 +434,10 @@ class PlayerData {
 
     const elementStack: any[] = [{
       element: this.video,
-      type: 'video'
+      type: 'video',
+      tagName: 'video',
+      classList: this.video.classList,
+      id: this.video.id,
     }];
 
     // first pass to generate the element stack and translate it into array
@@ -456,7 +466,7 @@ class PlayerData {
       // if 'verbose' option is passed, we also populate the elementStack
       // with heuristics data for auto player detection.
       if (playerCandidate && !options?.verbose) {
-        return playerCandidate;
+        return playerCandidate.element;
       }
     }
 
@@ -464,9 +474,12 @@ class PlayerData {
       // remember — we're only populating elementStack. If we found a player
       // element using manual methods, we will still return that element.
       this.getPlayerAuto(elementStack, videoWidth, videoHeight);
-      return playerCandidate;
+      playerCandidate.heuristics['activePlayer'] = true;
+      return playerCandidate.element;
     } else {
-      return this.getPlayerAuto(elementStack, videoWidth, videoHeight);
+      const playerCandidate = this.getPlayerAuto(elementStack, videoWidth, videoHeight);
+      playerCandidate.heuristics['activePlayer'] = true;
+      return playerCandidate.element;
     }
   }
 
@@ -545,7 +558,7 @@ class PlayerData {
     if (bestCandidate.initialValue) {
       bestCandidate = null;
     } else {
-      bestCandidate = bestCandidate.element;
+      bestCandidate.heuristics['autoMatch'] = true;
     }
 
     return bestCandidate;
@@ -587,7 +600,7 @@ class PlayerData {
     if (bestCandidate.initialValue) {
       bestCandidate = null;
     } else {
-      bestCandidate = bestCandidate.element;
+      bestCandidate.heuristics['qsMatch'] = true;
     }
 
     return bestCandidate;
@@ -596,11 +609,21 @@ class PlayerData {
   private getPlayerParentIndex(elementStack: any[]) {
     const host = window.location.hostname;
     elementStack[this.settings.active.sites[host].DOM.player.videoAncestor].heuristics['manualElementByParentIndex'] = true;
-    return elementStack[this.settings.active.sites[host].DOM.player.videoAncestor].element;
+    return elementStack[this.settings.active.sites[host].DOM.player.videoAncestor];
   }
 
-  equalish(a,b, tolerance) {
-    return a > b - tolerance && a < b + tolerance;
+  private handlePlayerTreeRequest() {
+    // this populates this.elementStack fully
+    this.getPlayer({verbose: true});
+
+    console.info('player-tree: emitting stack:', this.elementStack);
+    this.eventBus.send('uw-config-broadcast', {type: 'player-tree', config: JSON.parse(JSON.stringify(this.elementStack))});
+  }
+
+  private markElement(data: {parentIndex: number, enable: boolean}) {
+    console.log('mark element: got request to do border around this:', data);
+    this.elementStack[data.parentIndex].element.style.outline = data.enable ? '5px dashed #fa6' : null;
+    this.elementStack[data.parentIndex].element.style.filter = data.enable ? 'sepia(1) brightness(2) contrast(0.5)' : null;
   }
 
   forceRefreshPlayerElement() {
diff --git a/src/ext/lib/video-data/VideoData.ts b/src/ext/lib/video-data/VideoData.ts
index b060a14..c6fa4ce 100644
--- a/src/ext/lib/video-data/VideoData.ts
+++ b/src/ext/lib/video-data/VideoData.ts
@@ -94,6 +94,7 @@ class VideoData {
       this.eventBus.setUpstreamBus(pageInfo.eventBus);
     }
 
+
     this.setupStageOne();
   }
 
@@ -618,7 +619,7 @@ class VideoData {
     return heightCompensationFactor;
   }
 
-  //#region AARD handlers
+  //#region AARD handlers — TODO: remove, AARD handlers shouldn't be here
   initArDetection() {
     if(this.destroyed || this.invalid) {
       // throw {error: 'VIDEO_DATA_DESTROYED', data: {videoData: this}};
@@ -748,6 +749,16 @@ class VideoData {
 
     return false;
   }
+
+  /**
+   * Returns:
+   *    * number of parent elements on route from <video> to <body>
+   *    * parent index of automatically detected player element
+   *    * index of current player element
+   */
+  getPageOutline() {
+
+  }
 }
 
 export default VideoData;