show message about ClipboardItem support #50

for Firefox

src/views/Main/Workspace/Tabs/Tab/DataView/Pivot/index.vue

@@ -176,8 +176,7 @@ export default {
         const canvas = await getPivotCanvas(this.$refs.pivotOutput)
         cIo.copyCanvas(canvas)
       }
-    },
-
+    }
   }
 }
 </script>

src/views/Main/Workspace/Tabs/Tab/DataView/index.vue

@@ -107,7 +107,11 @@ export default {
       return this.$refs.viewComponent.getOptionsForSave()
     },
     copyToClipboard () {
+      if ('ClipboardItem' in window) {
         this.$refs.viewComponent.copyPngToClipboard()
+      } else {
+        alert ("Your browser doesn't support copying images into the clipboard. If you use Firefox you can enable it by setting dom.events.asyncClipboard.clipboardItem to true.")
+      }
     }
   }
 }