diff --git a/crates/egui/src/lib.rs b/crates/egui/src/lib.rs
index 9675fd69790..ae8e171daa8 100644
--- a/crates/egui/src/lib.rs
+++ b/crates/egui/src/lib.rs
@@ -460,7 +460,7 @@ pub use {
     layers::{LayerId, Order},
     layout::*,
     load::SizeHint,
-    memory::{Memory, Options, ThemePreference},
+    memory::{Memory, Options},
     painter::Painter,
     response::{InnerResponse, Response},
     sense::Sense,
diff --git a/crates/egui/src/memory.rs b/crates/egui/src/memory.rs
index f37e422b1b1..7fad4a5baab 100644
--- a/crates/egui/src/memory.rs
+++ b/crates/egui/src/memory.rs
@@ -5,7 +5,7 @@ use epaint::emath::TSTransform;
 
 use crate::{
     area, vec2, EventFilter, Id, IdMap, LayerId, Order, Pos2, Rangef, RawInput, Rect, Style, Vec2,
-    ViewportId, ViewportIdMap, ViewportIdSet,
+    ViewportId, ViewportIdMap, ViewportIdSet, Visuals,
 };
 
 // ----------------------------------------------------------------------------
@@ -1106,7 +1106,7 @@ impl Areas {
 /// Which theme should egui use?
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 #[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
-pub enum ThemePreference {
+pub(crate) enum ThemePreference {
     /// Dark mode: light text on a dark background.
     Dark,
 
@@ -1117,6 +1117,23 @@ pub enum ThemePreference {
     System,
 }
 
+impl ThemePreference {
+    pub(crate) fn from_dark_mode(dark_mode: bool) -> Self {
+        if dark_mode {
+            Self::Dark
+        } else {
+            Self::Light
+        }
+    }
+
+    pub(crate) fn into_visuals(self) -> Visuals {
+        match self {
+            Self::Dark | Self::System => Visuals::dark(),
+            Self::Light => Visuals::light(),
+        }
+    }
+}
+
 // ----------------------------------------------------------------------------
 
 #[test]
diff --git a/crates/egui/src/widgets/mod.rs b/crates/egui/src/widgets/mod.rs
index 8dbc8454f1d..d4cc2d702b7 100644
--- a/crates/egui/src/widgets/mod.rs
+++ b/crates/egui/src/widgets/mod.rs
@@ -41,7 +41,6 @@ pub use self::{
     slider::{Slider, SliderOrientation},
     spinner::Spinner,
     text_edit::{TextBuffer, TextEdit},
-    theme_switch::ThemeSwitch,
 };
 
 // ----------------------------------------------------------------------------
@@ -136,18 +135,10 @@ pub fn stroke_ui(ui: &mut crate::Ui, stroke: &mut epaint::Stroke, text: &str) {
 
 /// Show a small button to switch to/from dark/light mode (globally).
 pub fn global_dark_light_mode_switch(ui: &mut Ui) {
-    let mut theme = if ui.ctx().style().visuals.dark_mode {
-        ThemePreference::Dark
-    } else {
-        ThemePreference::Light
-    };
-    let response = ui.add(ThemeSwitch::new(&mut theme).show_follow_system(false));
+    let mut theme = memory::ThemePreference::from_dark_mode(ui.ctx().style().visuals.dark_mode);
+    let response = ui.add(theme_switch::ThemeSwitch::new(&mut theme).show_follow_system(false));
     if response.changed {
-        let visuals = match theme {
-            ThemePreference::Dark | ThemePreference::System => Visuals::dark(),
-            ThemePreference::Light => Visuals::light(),
-        };
-        ui.ctx().set_visuals(visuals);
+        ui.ctx().set_visuals(theme.into_visuals());
     }
 }
 
diff --git a/crates/egui/src/widgets/theme_switch/mod.rs b/crates/egui/src/widgets/theme_switch/mod.rs
index c24bd9fb48a..02997473c97 100644
--- a/crates/egui/src/widgets/theme_switch/mod.rs
+++ b/crates/egui/src/widgets/theme_switch/mod.rs
@@ -1,4 +1,5 @@
-use crate::{Painter, Response, ThemePreference, Ui, Widget};
+use crate::memory::ThemePreference;
+use crate::{Painter, Response, Ui, Widget};
 use emath::{Pos2, Rect};
 use epaint::Color32;
 
@@ -12,13 +13,13 @@ mod sun;
 /// preference (dark, light or follow system).
 #[must_use = "You should put this widget in an ui with `ui.add(widget);`"]
 #[derive(Debug)]
-pub struct ThemeSwitch<'a> {
+pub(crate) struct ThemeSwitch<'a> {
     value: &'a mut ThemePreference,
     show_follow_system: bool,
 }
 
 impl<'a> ThemeSwitch<'a> {
-    pub fn new(value: &'a mut ThemePreference) -> Self {
+    pub(crate) fn new(value: &'a mut ThemePreference) -> Self {
         Self {
             value,
             show_follow_system: true,
diff --git a/crates/egui_demo_lib/src/demo/widget_gallery.rs b/crates/egui_demo_lib/src/demo/widget_gallery.rs
index 1626488ad9b..2f59c7caee0 100644
--- a/crates/egui_demo_lib/src/demo/widget_gallery.rs
+++ b/crates/egui_demo_lib/src/demo/widget_gallery.rs
@@ -1,5 +1,3 @@
-use egui::{ThemePreference, ThemeSwitch};
-
 #[derive(Debug, PartialEq)]
 #[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 enum Enum {
@@ -20,7 +18,6 @@ pub struct WidgetGallery {
     string: String,
     color: egui::Color32,
     animate_progress_bar: bool,
-    theme: ThemePreference,
 
     #[cfg(feature = "chrono")]
     #[cfg_attr(feature = "serde", serde(skip))]
@@ -39,7 +36,6 @@ impl Default for WidgetGallery {
             string: Default::default(),
             color: egui::Color32::LIGHT_BLUE.linear_multiply(0.5),
             animate_progress_bar: false,
-            theme: ThemePreference::System,
             #[cfg(feature = "chrono")]
             date: None,
         }
@@ -123,7 +119,6 @@ impl WidgetGallery {
             animate_progress_bar,
             #[cfg(feature = "chrono")]
             date,
-            theme,
         } = self;
 
         ui.add(doc_link_label("Label", "label"));
@@ -253,10 +248,6 @@ impl WidgetGallery {
         });
         ui.end_row();
 
-        ui.add(doc_link_label("ThemeSwitch", "ThemeSwitch"));
-        ui.add(ThemeSwitch::new(theme));
-        ui.end_row();
-
         ui.add(doc_link_label_with_crate("egui_plot", "Plot", "plot"));
         example_plot(ui);
         ui.end_row();