Document PDF viewing feature

Documents settings needed to activate the feature that was added in
5.13.0

Fixes: QTBUG-75892
Change-Id: Ia4dbbc2e3c4f5a173d482dcae8ec5a1c31a8d6be
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@qt.io>
 
 

src/webengine/doc/src/qtwebengine-features.qdoc

@@ -44,6 +44,7 @@
         \li \l{HTTP/2 Protocol}
         \li \l{Native Dialogs}
         \li \l{Pepper Plugin API}
+        \li \l{PDF File Viewing}
         \li \l{Print to PDF}
         \li \l{Process Models}
         \li \l{Spellchecker}
@@ -319,6 +320,21 @@
     feature, the \c https://helpx.adobe.com/flash-player.html page can be opened
     in the browser.
 
+    \section1 PDF File Viewing
+
+    \QWE supports viewing PDF documents by navigating to them. This feature uses the Chromium
+    extensions API and PDF viewer plugin to display the PDF documents.
+    It can be tested in \l{WebEngine Widgets Simple Browser Example}{Simple Browser} or
+    \l{WebEngine Quick Nano Browser}{Nano Browser}.
+
+    Loading plugins needs to be enabled using QWebEngineSettings::PluginsEnabled or
+    WebEngineSettings::pluginsEnabled in order to use this feature.
+
+    This feature can be turned on (default) or off via the QWebEngineSettings::PdfViewerEnabled or
+    WebEngineSettings::pdfViewerEnabled setting.
+
+    Support for this feature was added in Qt 5.13.0.
+
     \section1 Print to PDF
 
     \QWE supports printing a web page to a PDF file. For more