fix: avoid insert embed tag on the main thread which cause Safari on Big Sur freezing

upgrade pdfobject to version 2.2.4

Signed-off-by: Max Wu <jackymaxj@gmail.com>

Author: jackycute

package-lock.json

@@ -173,7 +173,7 @@
     "nyc": "~14.0.0",
     "optimize-css-assets-webpack-plugin": "~5.0.0",
     "papaparse": "^5.2.0",
-    "pdfobject": "~2.1.1",
+    "pdfobject": "～2.2.4",
     "plantuml-encoder": "^1.2.5",
     "power-assert": "~1.6.1",
     "prismjs": "^1.17.1",

package.json

@@ -597,9 +597,11 @@ export function finishView (view) {
       const url = $(value).attr('data-pdfurl')
       const inner = $('<div></div>')
       $(this).append(inner)
-      PDFObject.embed(url, inner, {
-        height: '400px'
-      })
+      setTimeout(() => {
+        PDFObject.embed(url, inner, {
+          height: '400px'
+        })
+      }, 1)
     })
     // syntax highlighting
   view.find('code.raw').removeClass('raw')