refs #25980 [fid_adlr] js for resizing content area if getitbox (incl....

refs #25980 [fid_adlr] js for resizing content area if getitbox (incl. notices) are growing or shrinking
* replace DOMSubtreeModified event by MutationObserver
* move resizing into own function
** use .mainbody as reference element instead of .media
** consider padding of .mainbody for (re)calculating new min-width
** recalculate min-width of .mainbody on each call

themes/fid_adlr/templates/record/view.phtml

@@ -15,7 +15,7 @@
  * - remove record-tabs
  * - add back-to-search-link
  * - remove sidebar
- * - add specific JS to prevent get-it-box to protrude into footer #19260, #17831
+ * - add specific JS to prevent get-it-box to protrude into footer #19260, #17831, #25980
  * -- newsletter usage
  *
  * configured in: --
@@ -86,18 +86,25 @@
 
 <?= $this->inlineScript(\Laminas\View\Helper\HeadScript::SCRIPT, '$(document).ready(recordDocReady);', 'SET'); ?>
 
-<?php /* fid_adlr: specific JS to prevent get-it-box to protrude into footer #19260, #17831 */ ?>
+<?php /* fid_adlr: specific JS to prevent get-it-box to protrude into footer #19260, #17831, #25980 */ ?>
+<?php // fid_adlr: see jQuery Dimensions: https://www.w3schools.com/jquery/jquery_dimensions.asp ?>
 <?php $script = <<<JS
-  $(document).ready(function() {
-    $("body").on('DOMSubtreeModified', ".getitbox", function (){
-      if ($(window).width() >= 1200) { 
-      var contentHeight = $('.media').height();
-      var getitboxHeight = $('.getitbox').height();
-      if (getitboxHeight > contentHeight) {
-        $('.media').css('min-height', getitboxHeight+'px');
-      }
+  function resizeContentHeight() {
+    if ($(window).width() >= 1200) {
+      var getitbox = $('.getitbox');
+      var getitboxHeight = getitbox.height();
+      var content = $('.mainbody');
+      var contentAddition = content.outerHeight() - content.height();
+      content.css('min-height', Number(getitboxHeight + contentAddition)+'px');
     }
-   })   
+  }
+  $(document).ready(function() {
+    resizeContentHeight();
+    new MutationObserver(() => resizeContentHeight())
+      .observe(
+          $('.getitbox')[0],
+          { subtree: true, childList: true}
+      );
   });
 JS;
 ?>