diff --git a/packages/ludic.ui/attr_edge.ludic b/packages/ludic.ui/attr_edge.ludic
index a6417521..92f83eb0 100644
--- a/packages/ludic.ui/attr_edge.ludic
+++ b/packages/ludic.ui/attr_edge.ludic
@@ -55,7 +55,7 @@ function el_shadow(ui_st: mut UiState, n: UiNode, s: string) -> void {
       if nums == 0 { n.sh_x = el_unit(ui_st, p) }
       if nums == 1 { n.sh_y = el_unit(ui_st, p) }
       nums += 1
-    } else if col == "" { col = p } else { col = col + " " + p }
+    } else if col == "" { col = p } else { col = mm_join(ui_st, col, " ", p) }
   }
   if col == "" { col = "rgba(0,0,0,0.5)" }
   n.sh_c = ui_color(ui_st, col)
diff --git a/packages/ludic.ui/backend.ludic b/packages/ludic.ui/backend.ludic
index ec6857cd..cffed699 100644
--- a/packages/ludic.ui/backend.ludic
+++ b/packages/ludic.ui/backend.ludic
@@ -39,6 +39,7 @@ export state UiState {
   uv_false: Val = null
   mm: UiMemo = null                      # memo.ludic: splits, gradients and keys by their text
   mm_ints: []string = null
+  fc_none: Val = Value.null()            # focus.ludic: the value a key's down and up carry, made once
   mm_ivals: []Val = null
   ev_depth: int = 0                      # eval.ludic: a call's arguments, in lists kept one a depth
   ev_args: []Val = new []Val
diff --git a/packages/ludic.ui/focus.ludic b/packages/ludic.ui/focus.ludic
index e81b8eeb..01a1088c 100644
--- a/packages/ludic.ui/focus.ludic
+++ b/packages/ludic.ui/focus.ludic
@@ -49,12 +49,12 @@ function fc_keys(ui_st: mut UiState, root: UiNode) -> void {
 function fc_hold(ui_st: mut UiState, root: UiNode, n: UiNode) -> void {
   if ui_st.fr_key_press != "" and (ui_st.in_act_up or n.key != ui_st.fr_key_press) {
     let was = fr_node(root, ui_st.fr_key_press)
-    if was != null { ui_fire(ui_st, was, "up", Value.null()) }
+    if was != null { ui_fire(ui_st, was, "up", ui_st.fc_none) }
     ui_st.fr_key_press = ""
   }
   if ui_st.in_act_down and n.enabled {
     ui_st.fr_key_press = n.key
-    ui_fire(ui_st, n, "down", Value.null())
+    ui_fire(ui_st, n, "down", ui_st.fc_none)
   }
 }
 export function ui_focus(ui_st: mut UiState, key: string) -> void {
diff --git a/packages/ludic.ui/memo_join.ludic b/packages/ludic.ui/memo_join.ludic
index 3ec1fe38..94f77b70 100644
--- a/packages/ludic.ui/memo_join.ludic
+++ b/packages/ludic.ui/memo_join.ludic
@@ -36,14 +36,19 @@ function mm_join(ui_st: mut UiState, a: string, sep: string, b: string) -> strin
   m.slots[at] = len(m.keys)
   return k
 }
-# a small whole number's text, made once (a key's index, a loop's count)
+# a whole number's text, made once (a key's index, a count, money): 0..1023 at the start, the rest up
+# to MM_INT_MOST the first time each is shown; only past that is one made per call
+const MM_INT_MOST: int = 65536
 function mm_int(ui_st: mut UiState, i: int) -> string {
-  if i < 0 or i >= 1024 { return string(i) }
+  if i < 0 or i >= MM_INT_MOST { return string(i) }
   if ui_st.mm_ints == null {
     ui_st.mm_ints = new []string
     for k in 0 .. 1024 { push(ui_st.mm_ints, string(k)) }
   }
-  return ui_st.mm_ints[i]
+  let l = ui_st.mm_ints
+  while len(l) <= i { push(l, "") }
+  if i >= 1024 and len(l[i]) == 0 { l[i] = string(i) }
+  return l[i]
 }
 # a small whole number as a Value, made once and shared: read it, never change it (a loop's index)
 function mm_ival(ui_st: mut UiState, i: int) -> Val {
diff --git a/packages/ludic.ui/scroll_held.ludic b/packages/ludic.ui/scroll_held.ludic
index 45ab5f30..a0599e59 100644
--- a/packages/ludic.ui/scroll_held.ludic
+++ b/packages/ludic.ui/scroll_held.ludic
@@ -10,16 +10,20 @@ export function ui_scroll_set(ui_st: mut UiState, key: string, px: float) -> voi
 function sc_held(ui_st: mut UiState, n: UiNode, off: float, live: bool) -> float {
   var at = off
   if live {
-    let keys = new []string
-    let pxs = new []float
-    for i in 0 .. len(ui_st.sc_want_keys) {
-      if ui_st.sc_want_keys[i] == n.key or (n.id != "" and ui_st.sc_want_keys[i] == n.id) { at = ui_px(ui_st, ui_st.sc_want_px[i]) } else {
-        push(keys, ui_st.sc_want_keys[i])
-        push(pxs, ui_st.sc_want_px[i])
+    let keys = ui_st.sc_want_keys          # the asks for this box taken out in place, the others kept
+    let pxs = ui_st.sc_want_px
+    var kept = 0
+    for i in 0 .. len(keys) {
+      if keys[i] == n.key or (n.id != "" and keys[i] == n.id) { at = ui_px(ui_st, pxs[i]) } else {
+        keys[kept] = keys[i]
+        pxs[kept] = pxs[i]
+        kept += 1
       }
     }
-    ui_st.sc_want_keys = keys
-    ui_st.sc_want_px = pxs
+    while len(keys) > kept {
+      List.pop(keys)
+      List.pop(pxs)
+    }
   }
   let v = ui_attr(n, "scroll-top")
   if Value.kind(v) != 0 { at = ui_px(ui_st, el_numv(ui_st, v)) }