Fix SlimSelect dropdown scrolling regression

contao/templates/frontend/event_filter.html.twig

@@ -345,48 +345,31 @@
         return target.closest('.ss-content, .ss-list');
     };
 
-    const getOpenDropdown = () => {
-        const openContent = document.querySelector('.ss-content.ss-open');
-
-        if (openContent) {
-            return openContent;
-        }
-
-        const openMain = document.querySelector('.ss-main.ss-open');
-
-        if (!openMain) {
-            return null;
-        }
-
-        const scope = openMain.parentElement || document;
-        return scope.querySelector('.ss-content');
-    };
-
     const getScrollContainer = (targetDropdown) => {
-        const openDropdown = getOpenDropdown();
-
-        if (!openDropdown) {
+        if (!targetDropdown) {
             return null;
         }
 
-        if (!targetDropdown) {
-            return openDropdown;
+        if (targetDropdown.scrollHeight > targetDropdown.clientHeight) {
+            return targetDropdown;
         }
 
-        const contentContainer = targetDropdown.closest('.ss-content');
-        return contentContainer || openDropdown;
+        const contentContainer = targetDropdown.closest('.ss-content') || targetDropdown;
+        const listContainer = contentContainer.querySelector('.ss-list');
+
+        if (listContainer && listContainer.scrollHeight > listContainer.clientHeight) {
+            return listContainer;
+        }
+
+        if (contentContainer.scrollHeight > contentContainer.clientHeight) {
+            return contentContainer;
+        }
+
+        return null;
     };
 
     const shouldBlockBoundaryScroll = (scrollContainer, delta) => {
-        if (!scrollContainer) {
-            return false;
-        }
-
-        if (scrollContainer.scrollHeight <= scrollContainer.clientHeight) {
-            return true;
-        }
-
-        if (delta === 0) {
+        if (!scrollContainer || delta === 0) {
             return false;
         }
 
@@ -404,12 +387,12 @@
 
     document.addEventListener('wheel', (event) => {
         const dropdown = getDropdownFromTarget(event.target);
-        const scrollContainer = getScrollContainer(dropdown);
-
-        if (!scrollContainer) {
+        if (!dropdown) {
             return;
         }
 
+        const scrollContainer = getScrollContainer(dropdown);
+
         if (shouldBlockBoundaryScroll(scrollContainer, event.deltaY)) {
             event.preventDefault();
         }
@@ -419,9 +402,7 @@
 
     document.addEventListener('touchstart', (event) => {
         const dropdown = getDropdownFromTarget(event.target);
-        const scrollContainer = getScrollContainer(dropdown);
-
-        if (!scrollContainer || event.touches.length === 0) {
+        if (!dropdown || event.touches.length === 0) {
             lastTouchY = null;
             return;
         }
@@ -431,9 +412,13 @@
 
     document.addEventListener('touchmove', (event) => {
         const dropdown = getDropdownFromTarget(event.target);
+        if (!dropdown || event.touches.length === 0 || lastTouchY === null) {
+            return;
+        }
+
         const scrollContainer = getScrollContainer(dropdown);
 
-        if (!scrollContainer || event.touches.length === 0 || lastTouchY === null) {
+        if (!scrollContainer) {
             return;
         }