Bug 773942 - Hide the 'Open with Firefox' option if the download is started from the download button in pdf.js. r=Gijs

Differential Revision: https://phabricator.services.mozilla.com/D72779

toolkit/mozapps/downloads/HelperAppDlg.jsm

@@ -1240,7 +1240,13 @@ nsUnknownContentTypeDialog.prototype = {
   shouldShowInternalHandlerOption() {
     // This is currently available only for PDF files and when
     // pdf.js is enabled.
+    let browsingContext = this.mDialog.BrowsingContext.get(
+      this.mLauncher.browsingContextId
+    );
     return (
+      !browsingContext?.currentWindowGlobal?.documentPrincipal?.URI?.schemeIs(
+        "resource"
+      ) &&
       this.mLauncher.MIMEInfo.primaryExtension == "pdf" &&
       !Services.prefs.getBoolPref("pdfjs.disabled", true) &&
       Services.prefs.getBoolPref(

uriloader/exthandler/nsExternalHelperAppService.cpp

@@ -1275,6 +1275,12 @@ NS_IMETHODIMP nsExternalAppHandler::GetContentLength(int64_t* aContentLength) {
   return NS_OK;
 }
 
+NS_IMETHODIMP nsExternalAppHandler::GetBrowsingContextId(
+    uint64_t* aBrowsingContextId) {
+  *aBrowsingContextId = mBrowsingContext->Id();
+  return NS_OK;
+}
+
 void nsExternalAppHandler::RetargetLoadNotifications(nsIRequest* request) {
   // we are going to run the downloading of the helper app in our own little
   // docloader / load group context. so go ahead and force the creation of a

uriloader/exthandler/nsIExternalHelperAppService.idl

@@ -176,4 +176,9 @@ interface nsIHelperAppLauncher : nsICancelable
    * The download content length, or -1 if the length is not available.
    */
   readonly attribute int64_t contentLength;
+
+  /**
+   * The browsingContext ID of the launcher's source
+   */
+  readonly attribute uint64_t browsingContextId;
 };