diff --git a/library/layouts/VerticalTabsLayout.vue b/library/layouts/VerticalTabsLayout.vue
index 7db421ffa..b7fa34e25 100644
--- a/library/layouts/VerticalTabsLayout.vue
+++ b/library/layouts/VerticalTabsLayout.vue
@@ -390,7 +390,7 @@ const VTL_SHADOW_CSS = `
    composite that is meant to scroll — gets one. auto is load-bearing; scroll would paint a dead
    scrollbar on all 19 map tabs.
    overscroll-behavior:contain stops a wheel that bottoms out here from chaining to the document. */
-.vtl-host { position:absolute; inset:0; }
+.vtl-host { position:absolute; inset:0; overflow-y:auto; overflow-x:hidden; overscroll-behavior:contain; }
 /* The slot is the element's mount point. It must NOT be position:absolute; inset:0 any more: that
    pinned it to the pane's height and re-created the exact trap one level down — an absolutely
    positioned child cannot grow a scroll container. min-height:100% keeps a fixed-viewport map
@@ -812,7 +812,7 @@ export default defineComponent({
    composite that is meant to scroll — gets one. auto is load-bearing; scroll would paint a dead
    scrollbar on all 19 map tabs.
    overscroll-behavior:contain stops a wheel that bottoms out here from chaining to the document. */
-.vtl-host { position:absolute; inset:0; }
+.vtl-host { position:absolute; inset:0; overflow-y:auto; overflow-x:hidden; overscroll-behavior:contain; }
 /* The slot is the element's mount point. It must NOT be position:absolute; inset:0 any more: that
    pinned it to the pane's height and re-created the exact trap one level down — an absolutely
    positioned child cannot grow a scroll container. min-height:100% keeps a fixed-viewport map
diff --git a/plugin-designs/plugin-studio/plugin-studio.vue b/plugin-designs/plugin-studio/plugin-studio.vue
index a00be034c..c4b7937d3 100644
--- a/plugin-designs/plugin-studio/plugin-studio.vue
+++ b/plugin-designs/plugin-studio/plugin-studio.vue
@@ -190,7 +190,7 @@ const PS_SHADOW_CSS = `
    to own that scroll itself.
    auto, not scroll: only a pane whose content really exceeds its box gets a scrollbar, so the map
    tabs stay scrollbar-free (see the dvh floor note below, which is what makes that true). */
-.ps-pane { position:absolute; inset:0; }
+.ps-pane { position:absolute; inset:0; overflow-y:auto; overflow-x:hidden; overscroll-behavior:contain; }
 /* NOT absolute-inset: that pinned the mount point to the pane's height and re-created the same trap
    one level down (an absolutely positioned child cannot grow a scroll container). min-height:100%
    keeps a fixed-viewport map filling the pane while letting a taller composite grow it. */
@@ -631,7 +631,7 @@ export default defineComponent({
    position:absolute; inset:0 with the default overflow:visible inside an overflow:hidden stage.
    auto, not scroll: a fixed-viewport map fills the box exactly and gets NO scrollbar, so the map
    tabs are untouched. */
-.ps-pane { position: absolute; inset: 0; }
+.ps-pane { position:absolute; inset:0; overflow-y:auto; overflow-x:hidden; overscroll-behavior:contain; }
 /* NOT absolute-inset: that pinned the mount point to the pane's height and re-created the trap one
    level down. min-height:100% keeps a map filling the pane while letting a taller composite grow it. */
 .ps-slot { position: absolute; inset: 0; }