Only add Caption effect when needed

src/components/Clips.vue

@@ -154,11 +154,13 @@ export default {
           caption.caption_text += `${start_timestamp} --> ${end_timestamp}\n${clip.json.text}\n\n`
         }
       }
-      // Save caption effect
-      if (is_effect_new) {
-        await this.createEffect(effect_payload)
-      } else {
-        await this.updateEffect(effect_payload)
+      // Save caption effect (if any text is needed)
+      if (effect_payload.end > 0) {
+        if (is_effect_new) {
+          await this.createEffect(effect_payload)
+        } else {
+          await this.updateEffect(effect_payload)
+        }
       }
 
       // Create export