diff --git a/CMakeLists.txt b/CMakeLists.txt
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -29,6 +29,10 @@
 
 find_package(KF5 ${KF5_MIN_VERSION} COMPONENTS Activities DocTools) # Optional
 
+if(NOT Qt5WebEngineWidgets_VERSION VERSION_LESS "5.13.0")
+  add_definitions(-DWEBENGINE_PDF_VIEWER)
+endif()
+
 find_package(X11)
 set(KONQ_HAVE_X11 ${X11_FOUND})
 
diff --git a/settings/konqhtml/htmlopts.h b/settings/konqhtml/htmlopts.h
--- a/settings/konqhtml/htmlopts.h
+++ b/settings/konqhtml/htmlopts.h
@@ -49,6 +49,9 @@
     QCheckBox *m_pDoNotTrack;
     QCheckBox *m_pOfferToSaveWebsitePassword;
     KIntNumInput *m_pMaxFormCompletionItems;
+#ifdef WEBENGINE_PDF_VIEWER
+    QCheckBox *m_pdfViewer;
+#endif
 };
 
 #endif // HTMLOPTS_H
diff --git a/settings/konqhtml/htmlopts.cpp b/settings/konqhtml/htmlopts.cpp
--- a/settings/konqhtml/htmlopts.cpp
+++ b/settings/konqhtml/htmlopts.cpp
@@ -138,6 +138,13 @@
     connect(m_pOfferToSaveWebsitePassword, SIGNAL(toggled(bool)), SLOT(changed()));
     fl->addRow(m_pOfferToSaveWebsitePassword);
 
+#ifdef WEBENGINE_PDF_VIEWER
+    m_pdfViewer = new QCheckBox(i18n("Display online PDF files using WebEngine"));
+    m_pdfViewer->setWhatsThis(i18n("Uncheck this box to display online PDF files as configured in System Settings"));
+    fl->addRow(m_pdfViewer);
+    connect(m_pdfViewer, &QCheckBox::toggled, this, QOverload<>::of(&KMiscHTMLOptions::changed));
+#endif
+
     lay->addWidget(bgMisc);
     lay->addStretch(5);
 
@@ -167,6 +174,10 @@
     m_pMaxFormCompletionItems->setEnabled(m_pFormCompletionCheckBox->isChecked());
     m_pOfferToSaveWebsitePassword->setChecked(cg.readEntry("OfferToSaveWebsitePassword", true));
 
+#ifdef WEBENGINE_PDF_VIEWER
+    m_pdfViewer->setChecked(cg.readEntry("InternalPdfViewer", false));
+#endif
+
     cg2 = KConfigGroup(khtmlrcConfig, "Access Keys");
     m_pAccessKeys->setChecked(cg2.readEntry("Enabled", true));
 
@@ -188,6 +199,10 @@
     m_pOnlyMarkedBookmarksCheckBox->setChecked(false);
     m_pDoNotTrack->setChecked(false);
     m_pOfferToSaveWebsitePassword->setChecked(true);
+
+#ifdef WEBENGINE_PDF_VIEWER
+    m_pdfViewer->setChecked(false);
+#endif
 }
 
 void KMiscHTMLOptions::save()
@@ -202,6 +217,9 @@
     cg.writeEntry("FormCompletion", m_pFormCompletionCheckBox->isChecked());
     cg.writeEntry("MaxFormCompletionItems", m_pMaxFormCompletionItems->value());
     cg.writeEntry("OfferToSaveWebsitePassword", m_pOfferToSaveWebsitePassword->isChecked());
+#ifdef WEBENGINE_PDF_VIEWER
+    cg.writeEntry("InternalPdfViewer", m_pdfViewer->isChecked());
+#endif
     cg.sync();
 
     // Writes the value of m_pAccessKeys into khtmlrc to affect all applications using KHTML
diff --git a/webenginepart/src/settings/webenginesettings.h b/webenginepart/src/settings/webenginesettings.h
--- a/webenginepart/src/settings/webenginesettings.h
+++ b/webenginepart/src/settings/webenginesettings.h
@@ -125,6 +125,9 @@
     bool alowActiveMixedContent() const;
     bool allowMixedContentDisplay() const;
 
+    //Internal PDF viewer
+    bool internalPdfViewer() const;
+
     // Global config object stuff.
     static WebEngineSettings* self();
 
diff --git a/webenginepart/src/settings/webenginesettings.cpp b/webenginepart/src/settings/webenginesettings.cpp
--- a/webenginepart/src/settings/webenginesettings.cpp
+++ b/webenginepart/src/settings/webenginesettings.cpp
@@ -131,6 +131,7 @@
     QList< QPair< QString, QChar > > m_fallbackAccessKeysAssignments;
 
     KSharedConfig::Ptr nonPasswordStorableSites;
+    bool m_internalPdfViewer;
 };
 
 class WebEngineSettingsPrivate : public QObject, public WebEngineSettingsData
@@ -298,6 +299,11 @@
   return d->m_hoverLink;
 }
 
+bool WebEngineSettings::internalPdfViewer() const
+{
+    return d->m_internalPdfViewer;
+}
+
 void WebEngineSettings::init()
 {
   initWebEngineSettings();
@@ -485,6 +491,10 @@
         d->m_userSheet.clear();
     }
 
+    if (reset || cgHtml.hasKey("InternalPdfViewer")) {
+        d->m_internalPdfViewer = cgHtml.readEntry("InternalPdfViewer", false);
+    }
+
     d->m_formCompletionEnabled = cgHtml.readEntry("FormCompletion", true);
     d->m_maxFormCompletionItems = cgHtml.readEntry("MaxFormCompletionItems", 10);
     d->m_autoDelayedActionsEnabled = cgHtml.readEntry ("AutoDelayedActions", true);
@@ -706,6 +716,10 @@
 
   QWebEngineSettings::defaultSettings()->setAttribute(QWebEngineSettings::ScrollAnimatorEnabled, smoothScrolling() != KSmoothScrollingDisabled);
 
+#ifdef WEBENGINE_PDF_VIEWER
+  QWebEngineSettings::defaultSettings()->setAttribute(QWebEngineSettings::PdfViewerEnabled, internalPdfViewer());
+#endif
+
   // These numbers should be calculated from real "logical" DPI/72, using a default dpi of 96 for now
   computeFontSizes(96);
 }