diff --git a/web/themes/custom/geofresco/dist/js/responsive-iframes.js b/web/themes/custom/geofresco/dist/js/responsive-iframes.js
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+++ b/web/themes/custom/geofresco/dist/js/responsive-iframes.js
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+// From https://benmarshall.me/responsive-iframes/
+// Note that the JavaScript approach does not combine with his recommended CSS
+// approach, and it would probably be better/smoother to combine them.
+// @TODO Or, best, write a text formatter that does the below and assigns the
+// appropriate class, for example .embed-responsive-4by3
+
+// Find all iframes
+var $iframes = $( "iframe" );
+
+// Find and save the aspect ratio for all iframes
+$iframes.each(function () {
+  $( this ).data( "ratio", this.height / this.width )
+    // Remove the hardcoded width & height attributes
+    .removeAttr( "width" )
+    .removeAttr( "height" );
+});
+
+// Resize the iframes when the window is resized
+$( window ).resize( function () {
+  $iframes.each( function() {
+    // Get the parent container's width
+    var width = $( this ).parent().width();
+    $( this ).width( width )
+      .height( width * $( this ).data( "ratio" ) );
+  });
+// Resize to fix all iframes on page load.
+}).resize();