Closes #8

src/selection/SelectionHandler.js

@@ -49,6 +49,11 @@ export default class SelectionHandler extends EventEmitter {
         }
       } else {
         const selectedRange = trimRange(selection.getRangeAt(0));
+
+        // Make sure the selection is entirely inside this.el
+        const { commonAncestorContainer } = selectedRange;
+
+        if (this.el.contains(commonAncestorContainer)) {
           const stub = rangeToSelection(selectedRange, this.el);
 
           const spans = this.highlighter.wrapRange(selectedRange);
@@ -63,6 +68,7 @@ export default class SelectionHandler extends EventEmitter {
         }
       }
     }
+  }
 
   _clearNativeSelection = () => {
     if (window.getSelection) {