Updating z-index (will need a better mechanism for this)

Author: Angelina1984

dist/pdf-annotate.js

@@ -48,6 +48,7 @@ function createEditOverlay(target) {
   overlay.style.height = `${rect.height}px`;
   overlay.style.border = `${OVERLAY_BORDER_SIZE}px solid ${BORDER_COLOR}`;
   overlay.style.borderRadius = `${OVERLAY_BORDER_SIZE}px`;
+  overlay.style.zIndex = 20100;
 
   anchor.innerHTML = '×';
   anchor.setAttribute('href', 'javascript://');