Show first unstable element in autopilot

Skips all unstable elements in autopilot

client/src/app/shared/models/core/projector.ts

@@ -95,6 +95,18 @@ export class Projector extends BaseModel<Projector> {
         return [this.aspect_ratio_numerator, this.aspect_ratio_denominator].join(':');
     }
 
+    public get firstUnstableElement(): ProjectorElement {
+        let elementIndex = 0;
+        /**
+         * while we could use a filter function to remove all stable elements, I expect
+         * this approach to be the fastest
+         */
+        while (!!this.elements[elementIndex]?.stable) {
+            elementIndex++;
+        }
+        return this.elements[elementIndex] ?? null;
+    }
+
     /**
      * Set the aspect ratio
      */

client/src/app/site/cinema/components/cinema/cinema.component.ts

@@ -96,7 +96,7 @@ export class CinemaComponent extends BaseViewComponentDirective implements OnIni
         this.subscriptions.push(
             this.projectorRepo.getReferenceProjectorObservable().subscribe(refProjector => {
                 this.projector = refProjector;
-                this.currentProjectorElement = refProjector?.elements[0] || null;
+                this.currentProjectorElement = refProjector?.firstUnstableElement || null;
                 if (this.currentProjectorElement) {
                     this.projectedViewModel = this.projectorService.getViewModelFromProjectorElement(
                         this.currentProjectorElement