fix(pdf): highlights text layer is overlaid by the pdfjs built-in annotation layer

src/main/frontend/extensions/pdf/pdf.css

@@ -1000,11 +1000,6 @@ html.is-system-window {
 }
 
 .annotationLayer {
-  position: absolute;
-  top: 0;
-
-  z-index: 3;
-
   .highlightAnnotation, .underlineAnnotation {
     display: none;
   }