diff --git a/web/app.js b/web/app.js
index 4de56452c..354121b72 100644
--- a/web/app.js
+++ b/web/app.js
@@ -1858,7 +1858,7 @@ function webViewerInitialized() {
     file = "file" in params ? params.file : AppOptions.get("defaultUrl");
     validateFileURL(file);
   } else if (PDFJSDev.test("MOZCENTRAL")) {
-    file = window.location.href.split("#")[0];
+    file = window.location.href;
   } else if (PDFJSDev.test("CHROME")) {
     file = AppOptions.get("defaultUrl");
   }
diff --git a/web/pdf_attachment_viewer.js b/web/pdf_attachment_viewer.js
index de1a63df6..198162b93 100644
--- a/web/pdf_attachment_viewer.js
+++ b/web/pdf_attachment_viewer.js
@@ -95,7 +95,7 @@ class PDFAttachmentViewer {
         viewerUrl = "?file=" + encodeURIComponent(blobUrl + "#" + filename);
       } else if (PDFJSDev.test("MOZCENTRAL")) {
         // Let Firefox's content handler catch the URL and display the PDF.
-        viewerUrl = blobUrl + "?" + encodeURIComponent(filename);
+        viewerUrl = blobUrl + "#filename=" + encodeURIComponent(filename);
       } else if (PDFJSDev.test("CHROME")) {
         // In the Chrome extension, the URL is rewritten using the history API
         // in viewer.js, so an absolute URL must be generated.
diff --git a/web/ui_utils.js b/web/ui_utils.js
index 74ac2c633..c24ee9907 100644
--- a/web/ui_utils.js
+++ b/web/ui_utils.js
@@ -610,7 +610,7 @@ function getPDFFileNameFromURL(url, defaultFilename = "document.pdf") {
     return defaultFilename;
   }
   const reURI = /^(?:(?:[^:]+:)?\/\/[^\/]+)?([^?#]*)(\?[^#]*)?(#.*)?$/;
-  //            SCHEME        HOST         1.PATH  2.QUERY   3.REF
+  //              SCHEME        HOST         1.PATH  2.QUERY   3.REF
   // Pattern to get last matching NAME.pdf
   const reFilename = /[^\/?#=]+\.pdf\b(?!.*\.pdf\b)/i;
   const splitURI = reURI.exec(url);