diff --git a/src/components/Discover/Map/Filter/TimeframesFilter.vue b/src/components/Discover/Map/Filter/TimeframesFilter.vue
index d0f6afa..012156c 100644
--- a/src/components/Discover/Map/Filter/TimeframesFilter.vue
+++ b/src/components/Discover/Map/Filter/TimeframesFilter.vue
@@ -222,6 +222,7 @@ function resizeMask(chartInstance) {
 function resizeLeftMask(chartInstance, from) {
   const canvas = document.getElementById("chartCanvasId");
   const mask = document.getElementById("chart-mask-left");
+  if (!canvas || !mask) return;
   mask.style.left = `${canvas.offsetLeft + chartInstance.chartArea.left}px`;
   mask.style.width = `${chartInstance.chartArea.width * from}px`;
   mask.style.top = `${canvas.offsetTop + chartInstance.chartArea.top}px`;
@@ -235,6 +236,7 @@ function resizeLeftMask(chartInstance, from) {
 function resizeRightMask(chartInstance, to) {
   const canvas = document.getElementById("chartCanvasId");
   const mask = document.getElementById("chart-mask-right");
+  if (!canvas || !mask) return;
   mask.style.left = `${canvas.offsetLeft + chartInstance.chartArea.left + chartInstance.chartArea.width * to}px`;
   mask.style.width = `${chartInstance.chartArea.width * (1 - to)}px`;
   mask.style.top = `${canvas.offsetTop + chartInstance.chartArea.top}px`;