diff --git a/ui/src/debug/ControlBar.svelte b/ui/src/debug/ControlBar.svelte
index d9a8be2..a265af7 100644
--- a/ui/src/debug/ControlBar.svelte
+++ b/ui/src/debug/ControlBar.svelte
@@ -23,8 +23,6 @@
     export let groupingEnabled = true;
     export let onlyRelevantItems = true;
 
-    let { pagePinned } = pageControl;
-
     $: canNext = $debugStage + 1 < stageNames.length;
     $: canPrev = $debugStage > 0;
 </script>
diff --git a/ui/src/processParameters.ts b/ui/src/processParameters.ts
index 26f5a89..76df268 100644
--- a/ui/src/processParameters.ts
+++ b/ui/src/processParameters.ts
@@ -9,6 +9,9 @@ export function debugFromParams(defaultValue: boolean): boolean {
 }
 
 export function debugStageFromParams(defaultValue: number): number {
+    if (!params.has('stage')) {
+        return defaultValue;
+    }
     const stage = +params.get('stage');
     if (!Number.isInteger(stage)) {
         return defaultValue;