Merge pull request #13972 from Snuffleupagus/issue-13971

Treat all content as visible when no optional content groups are defined (issue 13971)

src/display/optional_content_config.js

@@ -95,6 +95,9 @@ class OptionalContentConfig {
   }
 
   isVisible(group) {
+    if (this._groups.size === 0) {
+      return true;
+    }
     if (!group) {
       warn("Optional content group not defined.");
       return true;

test/pdfs/issue13971.pdf.link

@@ -0,0 +1 @@
+https://github.com/mozilla/pdf.js/files/7109095/PDFBOX-5275-p5.pdf

test/test_manifest.json

@@ -3728,6 +3728,13 @@
        "link": true,
        "type": "eq"
     },
+    {  "id": "issue13971",
+       "file": "pdfs/issue13971.pdf",
+       "md5": "50fbf6b9f26ea0e4427f33bae62a4d77",
+       "rounds": 1,
+       "link": true,
+       "type": "eq"
+    },
     {  "id": "issue1655",
        "file": "pdfs/issue1655r.pdf",
        "md5": "569f48449ba57c15c4f9ade151a651c5",