diff --git a/scripts/build-plugins/rollup-plugin-build-themes.js b/scripts/build-plugins/rollup-plugin-build-themes.js
index 805590f4..f36db855 100644
--- a/scripts/build-plugins/rollup-plugin-build-themes.js
+++ b/scripts/build-plugins/rollup-plugin-build-themes.js
@@ -31,12 +31,13 @@ function appendVariablesToCSS(variables, cssSource) {
     return cssSource + getRootSectionWithVariables(variables);
 }
 
-function addThemesToConfig(bundle, themeSummary) {
+function addThemesToConfig(bundle, themeSummary, defaultThemes) {
     for (const [fileName, info] of Object.entries(bundle)) {
         if (fileName === "assets/config.json") {
             const source = new TextDecoder().decode(info.source);
             const config = JSON.parse(source);
             config["themes"] = themeSummary;
+            config["defaultTheme"] = defaultThemes;
             info.source = new TextEncoder().encode(JSON.stringify(config));
         }
     }
@@ -83,7 +84,7 @@ function parseBundle(bundle) {
 }
 
 module.exports = function buildThemes(options) {
-    let manifest, variants, defaultDark, defaultLight;
+    let manifest, variants, defaultDark, defaultLight,defaultThemes = {};
     let isDevelopment = false;
     const virtualModuleId = '@theme/'
     const resolvedVirtualModuleId = '\0' + virtualModuleId;
@@ -110,9 +111,11 @@ module.exports = function buildThemes(options) {
                         // This is the default theme, stash  the file name for later
                         if (details.dark) {
                             defaultDark = fileName;
+                            defaultThemes["dark"] = `${name}-${variant}`;
                         }
                         else {
                             defaultLight = fileName;
+                            defaultThemes["light"] = `${name}-${variant}`;
                         }
                     }
                     // emit the css as built theme bundle
@@ -274,7 +277,7 @@ module.exports = function buildThemes(options) {
                     themeSummary[`${name}-${variant}`] = assetHashedFileName;
                 });
             }
-            addThemesToConfig(bundle, themeSummary);
+            addThemesToConfig(bundle, themeSummary, defaultThemes);
             this.emitFile({
                 type: "asset",
                 name: "theme-summary.json",
diff --git a/src/domain/session/settings/SettingsViewModel.js b/src/domain/session/settings/SettingsViewModel.js
index 0bdb1355..083c209e 100644
--- a/src/domain/session/settings/SettingsViewModel.js
+++ b/src/domain/session/settings/SettingsViewModel.js
@@ -50,6 +50,7 @@ export class SettingsViewModel extends ViewModel {
         this.minSentImageSizeLimit = 400;
         this.maxSentImageSizeLimit = 4000;
         this.pushNotifications = new PushNotificationStatus();
+        this._activeTheme = undefined;
     }
 
     get _session() {
@@ -76,6 +77,7 @@ export class SettingsViewModel extends ViewModel {
         this.sentImageSizeLimit = await this.platform.settingsStorage.getInt("sentImageSizeLimit");
         this.pushNotifications.supported = await this.platform.notificationService.supportsPush();
         this.pushNotifications.enabled = await this._session.arePushNotificationsEnabled();
+        this._activeTheme = await this.platform.getActiveTheme();
         this.emitChange("");
     }
 
@@ -131,6 +133,10 @@ export class SettingsViewModel extends ViewModel {
         return this.platform.themes;
     }
 
+    get activeTheme() {
+        return this._activeTheme;
+    }
+
     setTheme(name) {
         this.platform.setTheme(name);
         this.platform.settingsStorage.setString("theme", name);
diff --git a/src/platform/web/Platform.js b/src/platform/web/Platform.js
index d1b96909..415081ba 100644
--- a/src/platform/web/Platform.js
+++ b/src/platform/web/Platform.js
@@ -319,6 +319,23 @@ export class Platform {
         return Object.keys(this.config["themes"]);
     }
 
+    async getActiveTheme() {
+        // check if theme is set via settings
+        let theme = await this.settingsStorage.getString("theme");
+        if (theme) {
+            return theme;
+        }
+        // return default theme
+        if (window.matchMedia) {
+            if (window.matchMedia("(prefers-color-scheme: dark)")) {
+                return this.config["defaultTheme"].dark;
+            } else if (window.matchMedia("(prefers-color-scheme: light)")) {
+                return this.config["defaultTheme"].light;
+            }
+        }
+        return undefined;
+    }
+
     setTheme(themeName) {
         const themeLocation = this.config["themes"][themeName];
         if (!themeLocation) {
diff --git a/src/platform/web/ui/session/settings/SettingsView.js b/src/platform/web/ui/session/settings/SettingsView.js
index b2c78f58..3e62bba6 100644
--- a/src/platform/web/ui/session/settings/SettingsView.js
+++ b/src/platform/web/ui/session/settings/SettingsView.js
@@ -97,7 +97,9 @@ export class SettingsView extends TemplateView {
         settingNodes.push(
             t.h3("Preferences"),
             row(t, vm.i18n`Scale down images when sending`, this._imageCompressionRange(t, vm)),
-            row(t, vm.i18n`Use the following theme`, this._themeOptions(t, vm)),
+            t.map(vm => vm.activeTheme, (theme, t) => {
+                return row(t, vm.i18n`Use the following theme`, this._themeOptions(t, vm, theme));
+            }),
         );
         settingNodes.push(
             t.h3("Application"),
@@ -137,10 +139,10 @@ export class SettingsView extends TemplateView {
         })];
     }
 
-    _themeOptions(t, vm) {
+    _themeOptions(t, vm, activeTheme) {
         const optionTags = [];
         for (const name of vm.themes) {
-            optionTags.push(t.option({value: name}, name));
+            optionTags.push(t.option({value: name, selected: name === activeTheme}, name));
         }
         return t.select({onChange: (e) => vm.setTheme(e.target.value)}, optionTags);
     }