diff --git a/frontend/src/components/EditorMarkdown.vue b/frontend/src/components/EditorMarkdown.vue
index 317cda26c..06b2dbe66 100644
--- a/frontend/src/components/EditorMarkdown.vue
+++ b/frontend/src/components/EditorMarkdown.vue
@@ -284,16 +284,16 @@
       <transition name="editor-markdown-preview">
         <div class="editor-markdown-preview" v-if="state.previewShown">
           <div class="editor-markdown-preview-toolbar">
-            <strong
+            <strong class="editor-markdown-preview-label"
               ><em>{{ t('editor.renderPreview') }}</em></strong
             >
-            <w-separator class="ml-4 mr-2" vertical inset />
+            <w-separator class="ml-4 mr-2" vertical inset dark />
             <w-btn
               icon="mdi:arrow-vertical-lock"
               padding="xs sm"
               flat
               @click="state.previewScrollSync = !state.previewScrollSync"
-              :color="state.previewScrollSync ? `primary` : null">
+              :color="state.previewScrollSync ? `secondary` : null">
               <w-tooltip anchor="top middle" self="bottom middle">{{
                 t('editor.toggleScrollSync')
               }}</w-tooltip>
@@ -1920,6 +1920,7 @@ function notImplemented() {
 
 <style lang="scss">
 @use 'sass:color';
+@use '@/css/_bricks.scss' as *;
 
 $editor-height: calc(100vh - 64px - 96px);
 $editor-preview-height: calc(100vh - 64px - 96px - 32px);
@@ -1998,20 +1999,37 @@ $editor-height-mobile: calc(100vh - 112px - 16px);
     &-leave-to {
       max-width: 0;
     }
+    /*
+      Dark in either appearance, where this used to follow the theme. Two reasons, and the second is
+      the one that settled it: the bar labels the render rather than being part of it, so a dark strip
+      reads as a caption on the pane instead of as more page; and the brickwork at its right end needs
+      a colour with room above it -- `$grey-3` is 93% lightness, so a seam brick a shade lighter than
+      it is white, which is a hole rather than a highlight.
+    */
     &-toolbar {
-      color: $grey-8;
       height: 32px;
       display: flex;
       align-items: center;
       padding: 0 1rem;
+      background-color: $dark-2;
+      color: $grey-6;
 
-      @at-root .body--light & {
-        background-color: $grey-3;
-      }
-      @at-root .body--dark & {
-        background-color: $dark-2;
-        color: $grey-6;
-      }
+      /*
+        -> The right end steps out of the bar's grey into the editor orange, as brickwork -- the same
+           treatment the Visual editor's toolbar gets, and for the same reason: the actions rail is
+           orange while an editor is open, and this bar runs up to it. `css/_bricks.scss` has the
+           whole of how and why.
+      */
+      @include brick-transition($dark-2);
+    }
+
+    /*
+      -> A shade lighter than the bar's own text colour, which the two icon buttons beside it still
+         take: this is the one piece of writing on the strip and what names the pane, so it carries
+         slightly more of the reader's attention than the controls do.
+    */
+    &-label {
+      color: $grey-5;
     }
     &-content {
       height: $editor-preview-height;
diff --git a/frontend/src/components/EditorVisual.vue b/frontend/src/components/EditorVisual.vue
index 1069c1ef0..467f67358 100644
--- a/frontend/src/components/EditorVisual.vue
+++ b/frontend/src/components/EditorVisual.vue
@@ -320,7 +320,7 @@
             }}</w-tooltip>
           </w-btn>
 
-          <w-space />
+          <w-separator class="mx-1" vertical inset dark />
 
           <w-btn dense icon="mdi:undo-variant" padding="xs sm" flat @click="runUndo">
             <w-tooltip anchor="top middle" self="bottom middle">{{
diff --git a/frontend/src/components/PageScriptsDialog.vue b/frontend/src/components/PageScriptsDialog.vue
index 1d410c18f..766f6658f 100644
--- a/frontend/src/components/PageScriptsDialog.vue
+++ b/frontend/src/components/PageScriptsDialog.vue
@@ -10,32 +10,50 @@
       </w-chip>
     </w-toolbar>
     <div style="min-height: 450px">
-      <!-- -> Square: this one spans the dialog edge to edge, so a radius would cut across its corners -->
+      <!--
+        -> Square: this one spans the dialog edge to edge, so a radius would cut across its corners.
+        -> Dark in either appearance: what is typed here is the page's own code rather than a wiki
+           setting, and a dark field is both what an author reads code in and what tells their code
+           apart from the dialog around it.
+      -->
       <util-code-editor
         ref="editor"
         v-model="state.content"
         :language="language"
         :min-height="450"
         :aria-label="languageLabel"
-        square />
+        square
+        dark />
     </div>
-    <w-card-actions class="card-actions">
+    <!--
+      Its own class rather than the shared `card-actions`: that one follows the app theme, and the
+      editor above is dark whichever theme is on -- a light bar under a dark pane reads as a different
+      component bolted to the bottom. Same treatment, and the same reasoning, as
+      `PageVersionSourceDialog`.
+    -->
+    <w-card-actions class="page-scripts-dialog-actions">
       <w-space />
+      <!-- -> `grey-5`, not the `grey-7` a light bar takes: #757575 on this bar is barely there -->
       <w-btn
         class="acrylic-btn"
         icon="la:times"
         :label="t(`common.actions.discard`)"
-        color="grey-7"
+        color="grey-5"
         padding="xs md"
         flat
         @click="$emit('close')" />
+      <!--
+        -> Apply, not Save: this writes the content into the page store and closes. Nothing reaches
+           the server until the page itself is saved, and a button saying otherwise invites an author
+           to close the editor believing their script is stored.
+      -->
       <w-btn
         icon="la:check"
-        :label="t(`common.actions.save`)"
+        :label="t(`common.actions.apply`)"
         unelevated
         color="primary"
         padding="xs md"
-        @click="saveAndClose" />
+        @click="applyAndClose" />
     </w-card-actions>
   </w-card>
 </template>
@@ -133,7 +151,7 @@ function persist() {
   EXPRESSION, and oxfmt reformats a semicolon-separated pair onto separate lines without the
   semicolon, which stops being one. It broke the build twice while this file was being edited.
 */
-function saveAndClose() {
+function applyAndClose() {
   persist()
   emit('close')
 }
@@ -152,4 +170,13 @@ onMounted(() => {
 })
 </script>
 
-<style lang="scss"></style>
+<style lang="scss">
+/* -> Colour only: WCardActions already lays the bar out */
+.page-scripts-dialog-actions {
+  background-color: $dark-3;
+  background-image: radial-gradient(at top left, $dark-3, $dark-5);
+  border-top: 1px solid #000;
+  box-shadow: 0 -1px 0 0 rgba(#fff, 0.06);
+  color: #fff;
+}
+</style>
diff --git a/frontend/src/components/UtilCodeEditor.vue b/frontend/src/components/UtilCodeEditor.vue
index bc85e00b1..8b9293b84 100644
--- a/frontend/src/components/UtilCodeEditor.vue
+++ b/frontend/src/components/UtilCodeEditor.vue
@@ -11,7 +11,7 @@
   -->
   <div
     class="util-code-editor"
-    :class="{ 'util-code-editor--square': square }"
+    :class="{ 'util-code-editor--square': square, 'util-code-editor--dark': dark }"
     :style="{ height: `${minHeight}px`, '--util-code-editor-gutter': gutterWidth }">
     <pre class="util-code-editor-view" aria-hidden="true"><code v-html="highlighted" /></pre>
     <textarea
@@ -88,6 +88,19 @@ const props = defineProps({
   square: {
     type: Boolean,
     default: false
+  },
+  /**
+   * Draw dark whatever appearance the rest of the interface is in.
+   *
+   * For a field whose CONTENT is code rather than a setting that happens to be typed -- the page's
+   * own scripts and styles -- where a dark field is what the author is used to reading code in and
+   * what separates their code from the wiki's chrome around it. The editor otherwise follows
+   * `body--dark` like everything else, so this only ever adds the dark palette; there is no light
+   * counterpart, because nothing wants a light field on a dark page.
+   */
+  dark: {
+    type: Boolean,
+    default: false
   }
 })
 
@@ -435,22 +448,26 @@ defineExpose({
   }
 }
 
-body.body--dark {
-  .util-code-editor {
-    border-color: rgb(255 255 255 / 0.3);
-    background-color: $dark-5;
-    background-image: linear-gradient(
-      to right,
-      $dark-4 0,
-      $dark-4 var(--util-code-editor-gutter),
-      rgb(255 255 255 / 0.12) var(--util-code-editor-gutter),
-      rgb(255 255 255 / 0.12) calc(var(--util-code-editor-gutter) + 1px),
-      transparent calc(var(--util-code-editor-gutter) + 1px)
-    );
-
-    &:focus-within {
-      border-color: var(--color-primary);
-    }
+/*
+  The dark appearance, as a mixin because two different things ask for it: the interface being in
+  dark mode, and the `dark` prop asking for a dark field regardless. Everything is written relative
+  to the root element -- the layers and the gutter numbers are its descendants -- so that one body
+  serves both selectors below.
+*/
+@mixin util-code-editor-dark {
+  border-color: rgb(255 255 255 / 0.3);
+  background-color: $dark-5;
+  background-image: linear-gradient(
+    to right,
+    $dark-4 0,
+    $dark-4 var(--util-code-editor-gutter),
+    rgb(255 255 255 / 0.12) var(--util-code-editor-gutter),
+    rgb(255 255 255 / 0.12) calc(var(--util-code-editor-gutter) + 1px),
+    transparent calc(var(--util-code-editor-gutter) + 1px)
+  );
+
+  &:focus-within {
+    border-color: var(--color-primary);
   }
 
   .util-code-editor-view {
@@ -465,54 +482,65 @@ body.body--dark {
     caret-color: #e6edf3;
   }
 
-  .util-code-editor {
-    .hljs-comment,
-    .hljs-quote {
-      color: #8b949e;
-    }
-    .hljs-keyword,
-    .hljs-selector-tag,
-    .hljs-literal,
-    .hljs-doctag,
-    .hljs-formula {
-      color: #ff7b72;
-    }
-    .hljs-string,
-    .hljs-regexp,
-    .hljs-addition,
-    .hljs-selector-attr,
-    .hljs-selector-pseudo {
-      color: #a5d6ff;
-    }
-    .hljs-number,
-    .hljs-variable,
-    .hljs-template-variable,
-    .hljs-symbol,
-    .hljs-bullet,
-    .hljs-attr,
-    .hljs-meta {
-      color: #79c0ff;
-    }
-    .hljs-title,
-    .hljs-section,
-    .hljs-selector-id,
-    .hljs-selector-class {
-      color: #d2a8ff;
-    }
-    .hljs-built_in,
-    .hljs-type,
-    .hljs-attribute,
-    .hljs-property,
-    .hljs-params {
-      color: #ffa657;
-    }
-    .hljs-name,
-    .hljs-tag {
-      color: #7ee787;
-    }
-    .hljs-deletion {
-      color: #ffa198;
-    }
+  .hljs-comment,
+  .hljs-quote {
+    color: #8b949e;
+  }
+  .hljs-keyword,
+  .hljs-selector-tag,
+  .hljs-literal,
+  .hljs-doctag,
+  .hljs-formula {
+    color: #ff7b72;
+  }
+  .hljs-string,
+  .hljs-regexp,
+  .hljs-addition,
+  .hljs-selector-attr,
+  .hljs-selector-pseudo {
+    color: #a5d6ff;
+  }
+  .hljs-number,
+  .hljs-variable,
+  .hljs-template-variable,
+  .hljs-symbol,
+  .hljs-bullet,
+  .hljs-attr,
+  .hljs-meta {
+    color: #79c0ff;
+  }
+  .hljs-title,
+  .hljs-section,
+  .hljs-selector-id,
+  .hljs-selector-class {
+    color: #d2a8ff;
   }
+  .hljs-built_in,
+  .hljs-type,
+  .hljs-attribute,
+  .hljs-property,
+  .hljs-params {
+    color: #ffa657;
+  }
+  .hljs-name,
+  .hljs-tag {
+    color: #7ee787;
+  }
+  .hljs-deletion {
+    color: #ffa198;
+  }
+}
+
+body.body--dark .util-code-editor {
+  @include util-code-editor-dark;
+}
+
+/*
+  -> Both classes, not just the modifier: the light palette above is `.util-code-editor .hljs-*`, two
+     classes, so a single-class modifier would tie with it and be settled by which rule the bundler
+     emitted last. Naming the root twice puts this one ahead on specificity rather than on luck.
+*/
+.util-code-editor.util-code-editor--dark {
+  @include util-code-editor-dark;
 }
 </style>
diff --git a/frontend/src/css/_bricks.scss b/frontend/src/css/_bricks.scss
new file mode 100644
index 000000000..06a604935
--- /dev/null
+++ b/frontend/src/css/_bricks.scss
@@ -0,0 +1,116 @@
+/*
+  The brick transition: a toolbar whose right end stops being its own colour and becomes the editor's
+  orange, through a staircase of brickwork rather than a straight edge.
+
+  Used by the Visual editor's toolbar and the Markdown editor's preview toolbar, which is the whole
+  reason this is a partial rather than a rule in either of them.
+*/
+
+/*
+  The Sass variables, loaded explicitly. `vite.config.js` injects `theme` and `palette` into every SFC
+  through `additionalData`, but that reaches only the files Vite itself hands to Sass -- a partial
+  pulled in by `@use` arrives without them. Same note as `_visual-editor.scss` and `_page-contents.scss`.
+*/
+@use 'sass:color';
+@use 'palette' as *;
+
+/**
+ * Lay the right end of a bar as brickwork stepping from `$cold` into `$hot`.
+ *
+ * Read the bar as five courses of brick. Counting in from the right edge, the last column has all
+ * five of its bricks knocked out, the one before it four, then three, then two, then one -- so the
+ * hot colour behind shows through as a staircase climbing to the right, the cold one thinning course
+ * by course until the corner is hot all the way up.
+ *
+ * Where the two meet, the brick on either side of the step is laid in a lighter shade of its own
+ * colour: one lighter cold and one lighter hot per course, each a single brick, so the seam reads as
+ * two diagonals of highlighted brick running with the step rather than as a hard edge. In every
+ * course the hot colour reaches column N and the cold one starts at N+1, which is what makes each of
+ * those runs a clean diagonal.
+ *
+ * Fifteen background layers rather than a clip path or an SVG, in three groups. The last five are the
+ * staircase: each one step, a hot rectangle anchored to the bottom-right corner, differing only in
+ * `background-size` -- one brick wide by five courses tall, two by four, three by three, four by two,
+ * five by one -- overlapping into the shape rather than tiling it, which is why they need no
+ * coordinates of their own. The first ten are the seam, one brick each, and those DO need
+ * coordinates: they are placed by offset from the right and top edges, a brick further along both per
+ * course. Earlier layers paint over later ones, so the seam is listed first.
+ *
+ * Courses are percentages, so there are five of them whatever the bar's height turns out to be. A
+ * brick's WIDTH is not a share of anything, so it comes from `$height` -- and a brick is square, which
+ * makes the staircase exactly as wide as the bar is tall, its diagonal a true 45 degrees, and the
+ * seam's offsets one and the same measure in both directions.
+ *
+ * `$deep-orange-9` is the default hot colour because that is what the actions rail turns while an
+ * editor is open (`PageActionsCol`): the rail and the bar are on screen together, at opposite edges of
+ * the same editor, so a second orange between them would read as a mistake rather than as a pair.
+ *
+ * The cold seam is emitted as a custom property, not baked into the layers, so that a bar whose own
+ * colour changes with the theme can restate just that one line in its dark branch instead of the
+ * whole stack. `$cold` is still required: it is what makes the default right for the common case, and
+ * an unset `var()` here would take the entire `background-image` down with it.
+ *
+ * @param {Color} $cold The bar's own background colour, which the brickwork steps out of.
+ * @param {Color} $hot The colour it steps into.
+ * @param {Length} $height The bar's height. Five courses are cut from it, and a brick is one square.
+ */
+@mixin brick-transition($cold, $hot: $deep-orange-9, $height: 32px) {
+  --brick: calc(#{$height} / 5);
+  --seam-cold: #{color.adjust($cold, $lightness: 10%)};
+  --seam-hot: #{color.adjust($hot, $lightness: 10%)};
+
+  background-image:
+    /* -> The seam, cold side: the last cold brick of each course */
+    linear-gradient(var(--seam-cold), var(--seam-cold)),
+    linear-gradient(var(--seam-cold), var(--seam-cold)),
+    linear-gradient(var(--seam-cold), var(--seam-cold)),
+    linear-gradient(var(--seam-cold), var(--seam-cold)),
+    linear-gradient(var(--seam-cold), var(--seam-cold)),
+    /* -> The seam, hot side: the first hot brick of each course */
+    linear-gradient(var(--seam-hot), var(--seam-hot)),
+    linear-gradient(var(--seam-hot), var(--seam-hot)),
+    linear-gradient(var(--seam-hot), var(--seam-hot)),
+    linear-gradient(var(--seam-hot), var(--seam-hot)),
+    linear-gradient(var(--seam-hot), var(--seam-hot)),
+    /* -> The staircase */
+    linear-gradient($hot, $hot),
+    linear-gradient($hot, $hot),
+    linear-gradient($hot, $hot),
+    linear-gradient($hot, $hot),
+    linear-gradient($hot, $hot);
+  background-repeat: no-repeat;
+  background-position:
+    /* -> Cold side: course 1 sits one brick in from the right, and each course one further */
+    right calc(var(--brick) * 1) top calc(var(--brick) * 0),
+    right calc(var(--brick) * 2) top calc(var(--brick) * 1),
+    right calc(var(--brick) * 3) top calc(var(--brick) * 2),
+    right calc(var(--brick) * 4) top calc(var(--brick) * 3),
+    right calc(var(--brick) * 5) top calc(var(--brick) * 4),
+    /* -> Hot side: the same diagonal, one column further right */
+    right calc(var(--brick) * 0) top calc(var(--brick) * 0),
+    right calc(var(--brick) * 1) top calc(var(--brick) * 1),
+    right calc(var(--brick) * 2) top calc(var(--brick) * 2),
+    right calc(var(--brick) * 3) top calc(var(--brick) * 3),
+    right calc(var(--brick) * 4) top calc(var(--brick) * 4),
+    right bottom,
+    right bottom,
+    right bottom,
+    right bottom,
+    right bottom;
+  background-size:
+    var(--brick) var(--brick),
+    var(--brick) var(--brick),
+    var(--brick) var(--brick),
+    var(--brick) var(--brick),
+    var(--brick) var(--brick),
+    var(--brick) var(--brick),
+    var(--brick) var(--brick),
+    var(--brick) var(--brick),
+    var(--brick) var(--brick),
+    var(--brick) var(--brick),
+    var(--brick) 100%,
+    calc(var(--brick) * 2) 80%,
+    calc(var(--brick) * 3) 60%,
+    calc(var(--brick) * 4) 40%,
+    calc(var(--brick) * 5) 20%;
+}
diff --git a/frontend/src/css/_visual-editor.scss b/frontend/src/css/_visual-editor.scss
index 7eb35428d..e068fbbf5 100644
--- a/frontend/src/css/_visual-editor.scss
+++ b/frontend/src/css/_visual-editor.scss
@@ -18,6 +18,7 @@
 @use 'sass:color';
 @use 'palette' as *;
 @use 'theme' as *;
+@use 'bricks' as *;
 
 /*
   A flex child of the article column, filling whatever it is given rather than a height of its own.
@@ -98,6 +99,12 @@
     background-color: $primary;
     color: #fff;
 
+    /*
+      -> The right end steps out of the bar's blue into the editor orange, as brickwork; the whole of
+         how and why is in `css/_bricks.scss`, which the Markdown editor's preview toolbar shares.
+    */
+    @include brick-transition($primary);
+
     /*
       What a pressed button looks like here. The `primary` colour these used to take is the colour of
       the bar itself, so an active button was drawn in the background it sits on and was simply