--- loncom/html/adm/help/tex/Course_Prefs_Display.tex	2021/12/24 14:19:38	1.9
+++ loncom/html/adm/help/tex/Course_Prefs_Display.tex	2022/08/28 02:41:30	1.10
@@ -11,6 +11,8 @@ converting \LaTeX{} to html.
         \item Student formula entry uses inline preview, not DragMath pop-up
         \item Molecule editor uses JSME (HTML5) in place of JME (Java)
         \item Chemical reaction response uses inline preview, not pop-up
+        \item Display of external resources
+\end{itemize}
 
 Style files (.sty extension) created in Authoring Space and published to the shared content pool
 can be selected for use when rendering resources in the course by clicking the 
@@ -38,6 +40,11 @@ The behavior of the textboxes where stud
 
 Similarly, the the molecular editor display will use the domain setting, unless overridden within a specific course.  If nothing is explicitly set in the domain or the course, then the default is to use JSME instead of its JME predecessor.
 
+The Course Editor can be used to add the URL for an external resource to be displayed within a LON-CAPA course. By default, the remote content will be displayed in an iframe with standard LON-CAPA menu links/icons present in the page header above the resource. LON-CAPA attempts to gracefully handle mixed active content issues for external resources by injecting usehttp=1 into the query string for the LON-CAPA URL, in order to force serving of an http:// external URL in an http:// LON-CAPA page, where the LON-CAPA server uses https:// by default for all other pages.  A separate session cookie which confers reduced rights is used when usehttp=1 is present in the query string because LON-CAPA's standard session cookie includes the 'secure' attribute.
 
-\end{itemize}
+LON-CAPA also attempts to circumvent the lack of scrolling for multi-page PDFs in iframes on iOS by replacing inline display in an iframe with a link when viewing on a mobile device.  Another instance where LON-CAPA replaces display of an external resource in an iframe with a link to display the resource in a separate browser tab is when Content-Security-Policy or X-Frame-Options prevent display in an iframe.
+
+The automatic display adjustments described above occur on a case-by-case basis depending on the external resource itself.
+
+The ``Display of external resources'' item can be used to force display of all external resources in a course in either a separate browser tab, or in a new browser window. In the latter case an optional width and height (in pixels) can be specified.  When tab or window are selected, there is also an option to re-use the same (named) tab or window when displaying different external resources in a course in order to limit the number of tabs or windows which may be created by browsing in a single course.