diff --git a/ui/src/components/CalendarImage.vue b/ui/src/components/CalendarImage.vue
index 1fc0c9b..e9ed740 100644
--- a/ui/src/components/CalendarImage.vue
+++ b/ui/src/components/CalendarImage.vue
@@ -19,8 +19,8 @@
         :height="preview_rectangle.height"
       />
       <rect
-        v-for="rect in rectangles"
-        :key="rect.left"
+        v-for="(rect, index) in rectangles"
+        :key="'rect' + index"
         :x="rect.left"
         :y="rect.top"
         :width="rect.width"
@@ -115,7 +115,6 @@ export default class CalendarImage extends Vue {
 <style lang="scss" scoped>
 div#container {
   position: relative;
-  max-height: 100%;
   user-select: none;
 
   img#background {