Fix IconSelect grid overflow and scroll jump

- Set maxHeight dynamically based on available viewport space
- Clamp popup horizontally to stay within viewport
- Remove max-height CSS transition that caused scroll jumps
- Auto-close popup on ancestor scroll to prevent stale positioning

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/wled_controller/static/css/components.css

@@ -618,19 +618,15 @@ textarea:focus-visible {
 .icon-select-popup {
     position: fixed;
     z-index: 10000;
-    max-height: 0;
     overflow: hidden;
     opacity: 0;
-    transition: max-height 0.2s ease, opacity 0.15s ease, margin 0.2s ease;
-    margin-top: 0;
+    transition: opacity 0.15s ease;
+    pointer-events: none;
 }
 .icon-select-popup.open {
-    max-height: 600px;
     opacity: 1;
-    margin-top: 6px;
-}
-.icon-select-popup.open.settled {
     overflow-y: auto;
+    pointer-events: auto;
 }
 
 .icon-select-grid {

server/src/wled_controller/static/js/core/icon-select.js

@@ -18,14 +18,12 @@
  * Call sel.setValue(v) to change programmatically, sel.destroy() to remove.
  */
 
-import { t } from './i18n.js';
-
 const POPUP_CLASS = 'icon-select-popup';
 
 /** Close every open icon-select popup. */
 export function closeAllIconSelects() {
     document.querySelectorAll(`.${POPUP_CLASS}`).forEach(p => {
-        p.classList.remove('open', 'settled');
+        p.classList.remove('open');
     });
 }
 
@@ -78,7 +76,6 @@ export class IconSelect {
         this._popup = document.createElement('div');
         this._popup.className = POPUP_CLASS;
         this._popup.addEventListener('click', (e) => e.stopPropagation());
-        this._popup.addEventListener('transitionend', this._onTransitionEnd);
         this._popup.innerHTML = this._buildGrid();
         document.body.appendChild(this._popup);
 
@@ -86,7 +83,8 @@ export class IconSelect {
         this._popup.querySelectorAll('.icon-select-cell').forEach(cell => {
             cell.addEventListener('click', () => {
                 this.setValue(cell.dataset.value, true);
-                this._popup.classList.remove('open', 'settled');
+                this._popup.classList.remove('open');
+                this._removeScrollListener();
             });
         });
 
@@ -127,17 +125,32 @@ export class IconSelect {
 
     _positionPopup() {
         const rect = this._trigger.getBoundingClientRect();
-        this._popup.style.left = rect.left + 'px';
-        this._popup.style.width = Math.max(rect.width, 200) + 'px';
+        const gap = 6;               // visual gap between trigger and popup
+        const pad = 8;               // min distance from viewport edge
+        const popupW = Math.max(rect.width, 200);
+        const spaceBelow = window.innerHeight - rect.bottom - gap - pad;
+        const spaceAbove = rect.top - gap - pad;
 
-        // Check if there's enough space below, otherwise open upward
-        const spaceBelow = window.innerHeight - rect.bottom;
-        const spaceAbove = rect.top;
-        if (spaceBelow < 250 && spaceAbove > spaceBelow) {
+        // Determine direction
+        const openUp = spaceBelow < 200 && spaceAbove > spaceBelow;
+        const available = openUp ? spaceAbove : spaceBelow;
+
+        // Horizontal: clamp so popup doesn't overflow right edge
+        let left = rect.left;
+        if (left + popupW > window.innerWidth - pad) {
+            left = window.innerWidth - pad - popupW;
+        }
+        if (left < pad) left = pad;
+
+        this._popup.style.left = left + 'px';
+        this._popup.style.width = popupW + 'px';
+        this._popup.style.maxHeight = available + 'px';
+
+        if (openUp) {
             this._popup.style.top = '';
-            this._popup.style.bottom = (window.innerHeight - rect.top) + 'px';
+            this._popup.style.bottom = (window.innerHeight - rect.top + gap) + 'px';
         } else {
-            this._popup.style.top = rect.bottom + 'px';
+            this._popup.style.top = (rect.bottom + gap) + 'px';
             this._popup.style.bottom = '';
         }
     }
@@ -148,14 +161,39 @@ export class IconSelect {
         if (!wasOpen) {
             this._positionPopup();
             this._popup.classList.add('open');
+            this._addScrollListener();
         }
     }
 
-    _onTransitionEnd = (e) => {
-        if (e.propertyName === 'max-height' && this._popup.classList.contains('open')) {
-            this._popup.classList.add('settled');
-        }
+    /** Close popup when any scrollable ancestor scrolls (prevents stale position). */
+    _addScrollListener() {
+        if (this._scrollHandler) return;
+        this._scrollHandler = () => {
+            this._popup.classList.remove('open');
+            this._removeScrollListener();
         };
+        // Listen on capture phase to catch scroll on any ancestor
+        let el = this._trigger.parentNode;
+        this._scrollTargets = [];
+        while (el && el !== document) {
+            if (el.scrollHeight > el.clientHeight || el.classList?.contains('modal-content')) {
+                el.addEventListener('scroll', this._scrollHandler, { passive: true });
+                this._scrollTargets.push(el);
+            }
+            el = el.parentNode;
+        }
+        window.addEventListener('scroll', this._scrollHandler, { passive: true });
+        this._scrollTargets.push(window);
+    }
+
+    _removeScrollListener() {
+        if (!this._scrollHandler) return;
+        for (const el of this._scrollTargets) {
+            el.removeEventListener('scroll', this._scrollHandler);
+        }
+        this._scrollTargets = [];
+        this._scrollHandler = null;
+    }
 
     /** Change the value programmatically. */
     setValue(value, fireChange = false) {
@@ -175,7 +213,7 @@ export class IconSelect {
         this._popup.querySelectorAll('.icon-select-cell').forEach(cell => {
             cell.addEventListener('click', () => {
                 this.setValue(cell.dataset.value, true);
-                this._popup.classList.remove('open', 'settled');
+                this._popup.classList.remove('open');
             });
         });
         this._syncTrigger();
@@ -183,6 +221,7 @@ export class IconSelect {
 
     /** Remove the enhancement, restore native <select>. */
     destroy() {
+        this._removeScrollListener();
         this._trigger.remove();
         this._popup.remove();
         this._select.style.display = '';