diff --git a/packages/frontend-2/components/viewer/controls/Left.vue b/packages/frontend-2/components/viewer/controls/Left.vue
index 9e77dd420..4440740d3 100644
--- a/packages/frontend-2/components/viewer/controls/Left.vue
+++ b/packages/frontend-2/components/viewer/controls/Left.vue
@@ -166,9 +166,15 @@
     <!-- Panel Extension - Portal target for additional content -->
     <div
       id="panel-extension"
-      class="absolute z-50 left-[calc(100dvw-20rem)] md:left-72 max-h-[calc(100dvh-6rem)] md:max-h-[calc(100dvh-4rem)] empty:hidden w-64 top-1.5 bg-foundation border border-outline-2 rounded-lg overflow-hidden"
-      :style="`left: ${panelExtensionLeft} !important`"
+      class="absolute z-50 left-[calc(100dvw-20rem)] md:left-72 max-h-[calc(100dvh-6rem)] md:max-h-[calc(100dvh-4rem)] top-1.5 bg-foundation rounded-lg overflow-hidden"
+      :style="`left: ${panelExtensionLeft} !important; width: ${panelExtensionWidth}px;`"
     >
+      <!-- Resize handle for panel extension -->
+      <div
+        ref="panelExtensionResizeHandle"
+        class="absolute h-full max-h-[calc(100dvh-6rem)] md:max-h-[calc(100dvh-4rem)] w-4 transition border-r hover:border-r-[2px] border-outline-2 hover:border-primary hidden lg:flex items-center cursor-ew-resize z-30 right-0"
+        @mousedown="startPanelExtensionResizing"
+      />
       <PortalTarget name="panel-extension"></PortalTarget>
     </div>
   </aside>
@@ -212,49 +218,7 @@ const emit = defineEmits<{
   forceClosePanels: []
 }>()
 
-const width = ref(264)
-const scrollableControlsContainer = ref(null as Nullable<HTMLDivElement>)
-const height = ref(scrollableControlsContainer.value?.clientHeight)
-const isResizing = ref(false)
-const resizeHandle = ref(null)
 const { width: windowWidth } = useWindowSize()
-let startWidth = 0
-let startX = 0
-
-const startResizing = (event: MouseEvent) => {
-  if (isMobile.value) return
-  event.preventDefault()
-  isResizing.value = true
-  startX = event.clientX
-  startWidth = width.value
-}
-
-const throttledHandleMouseMove = useThrottleFn((event: MouseEvent) => {
-  if (isResizing.value) {
-    const diffX = event.clientX - startX
-    const newWidth = Math.max(
-      240,
-      Math.min(startWidth + diffX, Math.min(440, windowWidth.value * 0.5 - 60))
-    )
-    width.value = newWidth
-  }
-}, 150)
-
-if (import.meta.client) {
-  useResizeObserver(scrollableControlsContainer, (entries) => {
-    const { height: newHeight } = entries[0].contentRect
-    height.value = newHeight
-  })
-  useEventListener(resizeHandle, 'mousedown', startResizing)
-
-  useEventListener(document, 'mousemove', throttledHandleMouseMove)
-
-  useEventListener(document, 'mouseup', () => {
-    if (isResizing.value) {
-      isResizing.value = false
-    }
-  })
-}
 
 const { isIntercomEnabled } = useIntercomEnabled()
 const { resourceItems, modelsAndVersionIds } = useInjectedViewerLoadedResources()
@@ -263,6 +227,7 @@ const { isEnabled: isEmbedEnabled } = useEmbed()
 const breakpoints = useBreakpoints(TailwindBreakpoints)
 const isMobile = breakpoints.smaller('sm')
 const isTablet = breakpoints.smaller('lg')
+const isLargerThanLg = breakpoints.greater('lg')
 const { getTooltipProps } = useSmartTooltipDelay()
 const isSavedViewsEnabled = useAreSavedViewsEnabled()
 const isWorkspacesEnabled = useIsWorkspacesEnabled()
@@ -278,6 +243,74 @@ const {
 
 const { onPanelButtonClick } = useViewerPanelsUtilities()
 
+const width = ref(264)
+const panelExtensionWidth = ref(isMobile.value ? 200 : isLargerThanLg.value ? 300 : 256)
+const scrollableControlsContainer = ref(null as Nullable<HTMLDivElement>)
+const height = ref(scrollableControlsContainer.value?.clientHeight)
+const isResizing = ref(false)
+const isPanelExtensionResizing = ref(false)
+const resizeHandle = ref(null)
+const panelExtensionResizeHandle = ref(null)
+
+let startWidth = 0
+let startX = 0
+let startPanelExtensionWidth = 0
+let startPanelExtensionX = 0
+
+const startResizing = (event: MouseEvent) => {
+  if (isMobile.value) return
+  event.preventDefault()
+  isResizing.value = true
+  startX = event.clientX
+  startWidth = width.value
+}
+
+const startPanelExtensionResizing = (event: MouseEvent) => {
+  if (isMobile.value) return
+  event.preventDefault()
+  isPanelExtensionResizing.value = true
+  startPanelExtensionX = event.clientX
+  startPanelExtensionWidth = panelExtensionWidth.value
+}
+
+const throttledHandleMouseMove = useThrottleFn((event: MouseEvent) => {
+  if (isResizing.value) {
+    const diffX = event.clientX - startX
+    const newWidth = Math.max(
+      240,
+      Math.min(startWidth + diffX, Math.min(440, windowWidth.value * 0.5 - 60))
+    )
+    width.value = newWidth
+  } else if (isPanelExtensionResizing.value) {
+    const diffX = event.clientX - startPanelExtensionX
+    const newWidth = Math.max(
+      200,
+      Math.min(startPanelExtensionWidth + diffX, Math.min(400, windowWidth.value * 0.4))
+    )
+    panelExtensionWidth.value = newWidth
+  }
+}, 150)
+
+if (import.meta.client) {
+  useResizeObserver(scrollableControlsContainer, (entries) => {
+    const { height: newHeight } = entries[0].contentRect
+    height.value = newHeight
+  })
+  useEventListener(resizeHandle, 'mousedown', startResizing)
+  useEventListener(panelExtensionResizeHandle, 'mousedown', startPanelExtensionResizing)
+
+  useEventListener(document, 'mousemove', throttledHandleMouseMove)
+
+  useEventListener(document, 'mouseup', () => {
+    if (isResizing.value) {
+      isResizing.value = false
+    }
+    if (isPanelExtensionResizing.value) {
+      isPanelExtensionResizing.value = false
+    }
+  })
+}
+
 const hasActivePanel = computed(() => activePanel.value !== 'none')
 
 const allAutomationRuns = computed(() => {
diff --git a/packages/frontend-2/components/viewer/filters/property-selection/Panel.vue b/packages/frontend-2/components/viewer/filters/property-selection/Panel.vue
index cba5f61d0..c0dc23446 100644
--- a/packages/frontend-2/components/viewer/filters/property-selection/Panel.vue
+++ b/packages/frontend-2/components/viewer/filters/property-selection/Panel.vue
@@ -1,5 +1,5 @@
 <template>
-  <div class="h-full flex flex-col select-none">
+  <div class="h-full flex flex-col select-none border border-outline-2 rounded-lg">
     <ViewerFiltersPropertySelectionSearch
       v-model="searchQuery"
       placeholder="Search for a property..."