diff --git a/src/main/frontend/components/lazy_editor.cljs b/src/main/frontend/components/lazy_editor.cljs
index b48339c96e..4d132f5e32 100644
--- a/src/main/frontend/components/lazy_editor.cljs
+++ b/src/main/frontend/components/lazy_editor.cljs
@@ -14,7 +14,7 @@
 
 (defonce loaded? (atom false))
 
-(rum/defcs editor <
+(rum/defc editor <
   rum/reactive
   {:will-mount
    (fn [state]
@@ -30,20 +30,17 @@
                         (fn []
                           (reset! loaded? true)))
                       (reset! loaded? true)))))
-     (let [*loading? (atom true)
-           timeout (js/setTimeout #(reset! *loading? false) 0)]
-       (assoc state
-              ::loading? *loading?
-              ::timeout timeout)))
-   :will-unmount (fn [state]
-                   (js/clearTimeout (::timeout state))
-                   state)}
-  [state config id attr code options]
-  (let [*loading? (::loading? state)
-        loaded?' (rum/react loaded?)
+     state)}
+  [config id attr code options]
+  (let [loaded?' (rum/react loaded?)
         theme   (state/sub :ui/theme)
         code    (or code "")
         code    (string/replace-first code #"\n$" "")]      ;; See-also: #3410
-    (if (or (not loaded?') (rum/react *loading?))
-      (ui/loading "CodeMirror")
-      (@lazy-editor config id attr code theme options))))
+    (ui/lazy-visible
+     (fn []
+       (when loaded?' (@lazy-editor config id attr code theme options)))
+     {:trigger-once? true
+      :placeholder [:div
+                    {:style {:height (min
+                                      (* 23.2 (count (string/split-lines code)))
+                                      600)}}]})))
diff --git a/src/main/frontend/extensions/code.cljs b/src/main/frontend/extensions/code.cljs
index ba2983259f..e717623dd5 100644
--- a/src/main/frontend/extensions/code.cljs
+++ b/src/main/frontend/extensions/code.cljs
@@ -1,11 +1,9 @@
 (ns frontend.extensions.code
-  (:require [cljs-bean.core :as bean]
-            [clojure.string :as string]
-            ["codemirror" :as CodeMirror]
+  (:require ["codemirror" :as CodeMirror]
             ["codemirror/addon/edit/closebrackets"]
             ["codemirror/addon/edit/matchbrackets"]
-            ["codemirror/addon/selection/active-line"]
             ["codemirror/addon/hint/show-hint"]
+            ["codemirror/addon/selection/active-line"]
             ["codemirror/mode/apl/apl"]
             ["codemirror/mode/asciiarmor/asciiarmor"]
             ["codemirror/mode/asn.1/asn.1"]
@@ -128,20 +126,22 @@
             ["codemirror/mode/yaml-frontmatter/yaml-frontmatter"]
             ["codemirror/mode/yaml/yaml"]
             ["codemirror/mode/z80/z80"]
+            [cljs-bean.core :as bean]
+            [clojure.string :as string]
             [frontend.commands :as commands]
+            [frontend.config :as config]
             [frontend.db :as db]
             [frontend.extensions.calc :as calc]
-            [frontend.handler.editor :as editor-handler]
             [frontend.handler.code :as code-handler]
+            [frontend.handler.editor :as editor-handler]
+            [frontend.schema.handler.common-config :refer [Config-edn]]
             [frontend.state :as state]
             [frontend.util :as util]
-            [frontend.config :as config]
             [goog.dom :as gdom]
             [goog.object :as gobj]
-            [frontend.schema.handler.common-config :refer [Config-edn]]
             [malli.core :as m]
-            [rum.core :as rum]
-            [promesa.core :as p]))
+            [promesa.core :as p]
+            [rum.core :as rum]))
 
 ;; codemirror
 
@@ -466,7 +466,7 @@
                              (when e (util/stop e))
                              (let [esc? (gobj/get cm "escPressed")]
                                (when (or (= :file (state/get-current-route))
-                                       (not esc?))
+                                         (not esc?))
                                  (code-handler/save-code-editor!))
                                (state/set-block-component-editing-mode! false)
                                (state/set-state! :editor/code-block-context nil)
@@ -549,6 +549,7 @@
                            (fn [e]
                              (.stopPropagation e)))
         (.save editor)
+        (.setSize editor "100%" 600)
         (.refresh editor)))
     editor))