diff --git a/apps/client/src/translations/cn/translation.json b/apps/client/src/translations/cn/translation.json
index bcc0bc269..455723f0e 100644
--- a/apps/client/src/translations/cn/translation.json
+++ b/apps/client/src/translations/cn/translation.json
@@ -1621,7 +1621,10 @@
     "color-scheme": "颜色方案"
   },
   "code_block": {
-    "word_wrapping": "自动换行"
+    "word_wrapping": "自动换行",
+    "theme_none": "无语法高亮",
+    "theme_group_light": "浅色主题",
+    "theme_group_dark": "深色主题"
   },
   "classic_editor_toolbar": {
     "title": "格式化"
diff --git a/apps/client/src/translations/de/translation.json b/apps/client/src/translations/de/translation.json
index 8ec5097aa..ea17f0575 100644
--- a/apps/client/src/translations/de/translation.json
+++ b/apps/client/src/translations/de/translation.json
@@ -1573,7 +1573,10 @@
     "color-scheme": "Farbschema"
   },
   "code_block": {
-    "word_wrapping": "Wortumbruch"
+    "word_wrapping": "Wortumbruch",
+    "theme_none": "Keine Syntax-Hervorhebung",
+    "theme_group_light": "Helle Themen",
+    "theme_group_dark": "Dunkle Themen"
   },
   "classic_editor_toolbar": {
     "title": "Format"
diff --git a/apps/client/src/translations/en/translation.json b/apps/client/src/translations/en/translation.json
index 24f104441..683eb42b2 100644
--- a/apps/client/src/translations/en/translation.json
+++ b/apps/client/src/translations/en/translation.json
@@ -1827,7 +1827,10 @@
     "color-scheme": "Color Scheme"
   },
   "code_block": {
-    "word_wrapping": "Word wrapping"
+    "word_wrapping": "Word wrapping",
+    "theme_none": "No syntax highlighting",
+    "theme_group_light": "Light themes",
+    "theme_group_dark": "Dark themes"
   },
   "classic_editor_toolbar": {
     "title": "Formatting"
diff --git a/apps/client/src/translations/es/translation.json b/apps/client/src/translations/es/translation.json
index 46be1d55f..64951c3a6 100644
--- a/apps/client/src/translations/es/translation.json
+++ b/apps/client/src/translations/es/translation.json
@@ -1589,7 +1589,10 @@
     "color-scheme": "Esquema de color"
   },
   "code_block": {
-    "word_wrapping": "Ajuste de palabras"
+    "word_wrapping": "Ajuste de palabras",
+    "theme_none": "Sin resaltado de sintaxis",
+    "theme_group_light": "Temas claros",
+    "theme_group_dark": "Temas oscuros"
   },
   "classic_editor_toolbar": {
     "title": "Formato"
diff --git a/apps/client/src/translations/fr/translation.json b/apps/client/src/translations/fr/translation.json
index d7597a3ac..74335e936 100644
--- a/apps/client/src/translations/fr/translation.json
+++ b/apps/client/src/translations/fr/translation.json
@@ -1579,7 +1579,10 @@
     "color-scheme": "Jeu de couleurs"
   },
   "code_block": {
-    "word_wrapping": "Saut à la ligne automatique suivant la largeur"
+    "word_wrapping": "Saut à la ligne automatique suivant la largeur",
+    "theme_none": "Pas de coloration syntaxique",
+    "theme_group_light": "Thèmes clairs",
+    "theme_group_dark": "Thèmes sombres"
   },
   "classic_editor_toolbar": {
     "title": "Mise en forme"
diff --git a/apps/client/src/translations/pt_br/translation.json b/apps/client/src/translations/pt_br/translation.json
index a79d14844..8410e64db 100644
--- a/apps/client/src/translations/pt_br/translation.json
+++ b/apps/client/src/translations/pt_br/translation.json
@@ -1,5 +1,10 @@
 {
   "revisions": {
     "delete_button": ""
+  },
+  "code_block": {
+    "theme_none": "Sem destaque de sintaxe",
+    "theme_group_light": "Temas claros",
+    "theme_group_dark": "Temas escuros"
   }
 }
diff --git a/apps/client/src/translations/ro/translation.json b/apps/client/src/translations/ro/translation.json
index efaf270f2..25b073e9e 100644
--- a/apps/client/src/translations/ro/translation.json
+++ b/apps/client/src/translations/ro/translation.json
@@ -1585,7 +1585,10 @@
     "description": "Controlează evidențierea de sintaxă pentru blocurile de cod în interiorul notițelor text, notițele de tip cod nu vor fi afectate de aceste setări."
   },
   "code_block": {
-    "word_wrapping": "Încadrare text"
+    "word_wrapping": "Încadrare text",
+    "theme_none": "Fără evidențiere de sintaxă",
+    "theme_group_dark": "Teme întunecate",
+    "theme_group_light": "Teme luminoase"
   },
   "classic_editor_toolbar": {
     "title": "Formatare"
diff --git a/apps/client/src/translations/tw/translation.json b/apps/client/src/translations/tw/translation.json
index 4360fcdf4..c25504510 100644
--- a/apps/client/src/translations/tw/translation.json
+++ b/apps/client/src/translations/tw/translation.json
@@ -1519,7 +1519,10 @@
     "color-scheme": "顏色方案"
   },
   "code_block": {
-    "word_wrapping": "自動換行"
+    "word_wrapping": "自動換行",
+    "theme_none": "無格式高亮",
+    "theme_group_light": "淺色主題",
+    "theme_group_dark": "深色主題"
   },
   "classic_editor_toolbar": {
     "title": "格式化"
diff --git a/apps/client/src/widgets/type_widgets/options/text_notes/code_block.ts b/apps/client/src/widgets/type_widgets/options/text_notes/code_block.ts
index 59ae84743..d72385ecf 100644
--- a/apps/client/src/widgets/type_widgets/options/text_notes/code_block.ts
+++ b/apps/client/src/widgets/type_widgets/options/text_notes/code_block.ts
@@ -3,7 +3,7 @@ import { t } from "../../../../services/i18n.js";
 import server from "../../../../services/server.js";
 import OptionsWidget from "../options_widget.js";
 import { ensureMimeTypesForHighlighting, loadHighlightingTheme } from "../../../../services/syntax_highlight.js";
-import { Themes } from "@triliumnext/highlightjs";
+import { Themes, type Theme } from "@triliumnext/highlightjs";
 
 const SAMPLE_LANGUAGE = normalizeMimeTypeForCKEditor("application/javascript;env=frontend");
 const SAMPLE_CODE = `\
@@ -68,13 +68,28 @@ export default class CodeBlockOptions extends OptionsWidget {
     doRender() {
         this.$widget = $(TPL);
         this.$themeSelect = this.$widget.find(".theme-select");
+
         // Populate the list of themes.
-        for (const [ id, theme ] of Object.entries(Themes)) {
-            const option = $("<option>")
-                .attr("value", `default:${id}`)
-                .text(theme.name);
-            this.$themeSelect.append(option);
+        const themeGroups = groupThemesByLightOrDark();
+        for (const [key, themes] of Object.entries(themeGroups)) {
+            const $group = key ? $("<optgroup>").attr("label", key) : null;
+
+            for (const [id, theme] of Object.entries(themes)) {
+                const option = $("<option>")
+                    .attr("value", "default:" + id)
+                    .text(theme.name);
+
+                if ($group) {
+                    $group.append(option);
+                } else {
+                    this.$themeSelect.append(option);
+                }
+            }
+            if ($group) {
+                this.$themeSelect.append($group);
+            }
         }
+
         this.$themeSelect.on("change", async () => {
             const newTheme = String(this.$themeSelect.val());
             loadHighlightingTheme(newTheme);
@@ -113,3 +128,21 @@ export default class CodeBlockOptions extends OptionsWidget {
         this.#setupPreview(options.codeBlockTheme !== "none");
     }
 }
+
+function groupThemesByLightOrDark() {
+    const darkThemes: Record<string, Theme> = {};
+    const lightThemes: Record<string, Theme> = {};
+
+    for (const [ id, theme ] of Object.entries(Themes)) {
+        if (theme.name.includes("Dark")) {
+            darkThemes[id] = theme;
+        } else {
+            lightThemes[id] = theme;
+        }
+    }
+
+    const output: Record<string, Record<string, Theme>> = {};
+    output[t("code_block.theme_group_light")] = lightThemes;
+    output[t("code_block.theme_group_dark")] = darkThemes;
+    return output;
+}
diff --git a/apps/server/src/assets/translations/cn/server.json b/apps/server/src/assets/translations/cn/server.json
index 330853c0e..8af485c5d 100644
--- a/apps/server/src/assets/translations/cn/server.json
+++ b/apps/server/src/assets/translations/cn/server.json
@@ -193,11 +193,6 @@
   "special_notes": {
     "search_prefix": "搜索:"
   },
-  "code_block": {
-    "theme_none": "无语法高亮",
-    "theme_group_light": "浅色主题",
-    "theme_group_dark": "深色主题"
-  },
   "test_sync": {
     "not-configured": "同步服务器主机未配置。请先配置同步。",
     "successful": "同步服务器握手成功，同步已开始。"
diff --git a/apps/server/src/assets/translations/de/server.json b/apps/server/src/assets/translations/de/server.json
index 8cb8d38dd..5a299bb59 100644
--- a/apps/server/src/assets/translations/de/server.json
+++ b/apps/server/src/assets/translations/de/server.json
@@ -185,11 +185,6 @@
   "special_notes": {
     "search_prefix": "Suche:"
   },
-  "code_block": {
-    "theme_none": "Keine Syntax-Hervorhebung",
-    "theme_group_light": "Helle Themen",
-    "theme_group_dark": "Dunkle Themen"
-  },
   "test_sync": {
     "not-configured": "Der Synchronisations-Server-Host ist nicht konfiguriert. Bitte konfiguriere zuerst die Synchronisation.",
     "successful": "Die Server-Verbindung wurde erfolgreich hergestellt, die Synchronisation wurde gestartet."
diff --git a/apps/server/src/assets/translations/en/server.json b/apps/server/src/assets/translations/en/server.json
index df91eee91..2985cc010 100644
--- a/apps/server/src/assets/translations/en/server.json
+++ b/apps/server/src/assets/translations/en/server.json
@@ -193,11 +193,6 @@
   "special_notes": {
     "search_prefix": "Search:"
   },
-  "code_block": {
-    "theme_none": "No syntax highlighting",
-    "theme_group_light": "Light themes",
-    "theme_group_dark": "Dark themes"
-  },
   "test_sync": {
     "not-configured": "Sync server host is not configured. Please configure sync first.",
     "successful": "Sync server handshake has been successful, sync has been started."
diff --git a/apps/server/src/assets/translations/es/server.json b/apps/server/src/assets/translations/es/server.json
index b523a2b03..aaa725192 100644
--- a/apps/server/src/assets/translations/es/server.json
+++ b/apps/server/src/assets/translations/es/server.json
@@ -189,11 +189,6 @@
   "special_notes": {
     "search_prefix": "Buscar:"
   },
-  "code_block": {
-    "theme_none": "Sin resaltado de sintaxis",
-    "theme_group_light": "Temas claros",
-    "theme_group_dark": "Temas oscuros"
-  },
   "test_sync": {
     "not-configured": "El servidor de sincronización no está configurado. Por favor configure primero la sincronización.",
     "successful": "El protocolo de enlace del servidor de sincronización ha sido exitoso, la sincronización ha comenzado."
diff --git a/apps/server/src/assets/translations/fr/server.json b/apps/server/src/assets/translations/fr/server.json
index aaecbb5d2..9f9d527d2 100644
--- a/apps/server/src/assets/translations/fr/server.json
+++ b/apps/server/src/assets/translations/fr/server.json
@@ -189,11 +189,6 @@
   "special_notes": {
     "search_prefix": "Recherche :"
   },
-  "code_block": {
-    "theme_none": "Pas de coloration syntaxique",
-    "theme_group_light": "Thèmes clairs",
-    "theme_group_dark": "Thèmes sombres"
-  },
   "test_sync": {
     "not-configured": "L'hôte du serveur de synchronisation n'est pas configuré. Veuillez d'abord configurer la synchronisation.",
     "successful": "L'établissement de liaison du serveur de synchronisation a été réussi, la synchronisation a été démarrée."
diff --git a/apps/server/src/assets/translations/pt_br/server.json b/apps/server/src/assets/translations/pt_br/server.json
index fbca023e8..9a94fd357 100644
--- a/apps/server/src/assets/translations/pt_br/server.json
+++ b/apps/server/src/assets/translations/pt_br/server.json
@@ -186,11 +186,6 @@
   "special_notes": {
     "search_prefix": "Pesquisar:"
   },
-  "code_block": {
-    "theme_none": "Sem destaque de sintaxe",
-    "theme_group_light": "Temas claros",
-    "theme_group_dark": "Temas escuros"
-  },
   "test_sync": {
     "not-configured": "O host do servidor de sincronização não está configurado. Por favor, configure a sincronização primeiro.",
     "successful": "A comunicação com o servidor de sincronização foi bem-sucedida, a sincronização foi iniciada."
diff --git a/apps/server/src/assets/translations/ro/server.json b/apps/server/src/assets/translations/ro/server.json
index d7e54be29..70c9c30d9 100644
--- a/apps/server/src/assets/translations/ro/server.json
+++ b/apps/server/src/assets/translations/ro/server.json
@@ -189,11 +189,6 @@
   "special_notes": {
     "search_prefix": "Căutare:"
   },
-  "code_block": {
-    "theme_none": "Fără evidențiere de sintaxă",
-    "theme_group_dark": "Teme întunecate",
-    "theme_group_light": "Teme luminoase"
-  },
   "test_sync": {
     "not-configured": "Calea către serverul de sincronizare nu este configurată. Configurați sincronizarea înainte.",
     "successful": "Comunicarea cu serverul de sincronizare a avut loc cu succes, s-a început sincronizarea."
diff --git a/apps/server/src/assets/translations/tw/server.json b/apps/server/src/assets/translations/tw/server.json
index d30f92bd9..5ab2fcf28 100644
--- a/apps/server/src/assets/translations/tw/server.json
+++ b/apps/server/src/assets/translations/tw/server.json
@@ -185,11 +185,6 @@
   "special_notes": {
     "search_prefix": "搜尋："
   },
-  "code_block": {
-    "theme_none": "無格式高亮",
-    "theme_group_light": "淺色主題",
-    "theme_group_dark": "深色主題"
-  },
   "test_sync": {
     "not-configured": "並未設定同步伺服器主機，請先設定同步",
     "successful": "成功與同步伺服器握手，現在開始同步"
diff --git a/apps/server/src/services/code_block_theme.spec.ts b/apps/server/src/services/code_block_theme.spec.ts
deleted file mode 100644
index 3a255ff29..000000000
--- a/apps/server/src/services/code_block_theme.spec.ts
+++ /dev/null
@@ -1,22 +0,0 @@
-import { describe, expect, it } from "vitest";
-import { readThemesFromFileSystem } from "./code_block_theme.js";
-
-import themeNames from "./code_block_theme_names.json" with { type: "json" };
-import path = require("path");
-
-describe("Code block theme", () => {
-    it("all themes are mapped", () => {
-        const themes = readThemesFromFileSystem(path.join(__dirname, "../../node_modules/@highlightjs/cdn-assets/styles"));
-
-        const mappedThemeNames = new Set(Object.values(themeNames));
-        const unmappedThemeNames = new Set<string>();
-
-        for (const theme of themes) {
-            if (!mappedThemeNames.has(theme.title)) {
-                unmappedThemeNames.add(theme.title);
-            }
-        }
-
-        expect(unmappedThemeNames.size, `Unmapped themes: ${Array.from(unmappedThemeNames).join(", ")}`).toBe(0);
-    });
-});
diff --git a/apps/server/src/services/code_block_theme.ts b/apps/server/src/services/code_block_theme.ts
deleted file mode 100644
index f63510cad..000000000
--- a/apps/server/src/services/code_block_theme.ts
+++ /dev/null
@@ -1,102 +0,0 @@
-/**
- * @module
- *
- * Manages the server-side functionality of the code blocks feature, mostly for obtaining the available themes for syntax highlighting.
- */
-
-import fs from "fs";
-import { t } from "i18next";
-import { join } from "path";
-import { isDev, isElectron, getResourceDir } from "./utils.js";
-
-/**
- * Represents a color scheme for the code block syntax highlight.
- */
-interface ColorTheme {
-    /** The ID of the color scheme which should be stored in the options. */
-    val: string;
-    /** A user-friendly name of the theme. The name is already localized. */
-    title: string;
-}
-
-/**
- * Returns all the supported syntax highlighting themes for code blocks, in groups.
- *
- * The return value is an object where the keys represent groups in their human-readable name (e.g. "Light theme")
- * and the values are an array containing the information about every theme. There is also a special group with no
- * title (empty string) which should be displayed at the top of the listing pages, without a group.
- *
- * @returns the supported themes, grouped.
- */
-export function listSyntaxHighlightingThemes() {
-    const path = getStylesDirectory();
-    const systemThemes = readThemesFromFileSystem(path);
-
-    return {
-        "": [
-            {
-                val: "none",
-                title: t("code_block.theme_none")
-            }
-        ],
-        ...groupThemesByLightOrDark(systemThemes)
-    };
-}
-
-export function getStylesDirectory() {
-    if (isElectron && !isDev) {
-        return join(getResourceDir(), "styles");
-    } else if (!isDev) {
-        return join(getResourceDir(), "node_modules/@highlightjs/cdn-assets/styles");
-    } else {
-        return join(__dirname, "../node_modules/@highlightjs/cdn-assets/styles");
-    }
-}
-
-/**
- * Reads all the predefined themes by listing all minified CSSes from a given directory.
- *
- * The theme names are mapped against a known list in order to provide more descriptive names such as "Visual Studio 2015 (Dark)" instead of "vs2015".
- *
- * @param path the path to read from. Usually this is the highlight.js `styles` directory.
- * @returns the list of themes.
- */
-export function readThemesFromFileSystem(path: string): ColorTheme[] {
-    return fs
-        .readdirSync(path)
-        .filter((el) => el.endsWith(".min.css"))
-        .map((name) => {
-            const nameWithoutExtension = name.replace(".min.css", "");
-            let title = nameWithoutExtension.replace(/-/g, " ");
-
-            return {
-                val: `default:${nameWithoutExtension}`,
-                title: title
-            };
-        });
-}
-
-/**
- * Groups a list of themes by dark or light themes. This is done simply by checking whether "Dark" is present in the given theme, otherwise it's considered a light theme.
- * This generally only works if the theme has a known human-readable name (see {@link #readThemesFromFileSystem()})
- *
- * @param listOfThemes the list of themes to be grouped.
- * @returns the grouped themes by light or dark.
- */
-function groupThemesByLightOrDark(listOfThemes: ColorTheme[]) {
-    const darkThemes = [];
-    const lightThemes = [];
-
-    for (const theme of listOfThemes) {
-        if (theme.title.includes("Dark")) {
-            darkThemes.push(theme);
-        } else {
-            lightThemes.push(theme);
-        }
-    }
-
-    const output: Record<string, ColorTheme[]> = {};
-    output[t("code_block.theme_group_light")] = lightThemes;
-    output[t("code_block.theme_group_dark")] = darkThemes;
-    return output;
-}
diff --git a/packages/highlightjs/src/index.ts b/packages/highlightjs/src/index.ts
index 3815cf563..bc1b6b71a 100644
--- a/packages/highlightjs/src/index.ts
+++ b/packages/highlightjs/src/index.ts
@@ -4,7 +4,7 @@ import syntaxDefinitions from "./syntax_highlighting.js";
 import { type Theme } from "./themes.js";
 import { type HighlightOptions } from "highlight.js";
 
-export { default as Themes } from "./themes.js";
+export { default as Themes, type Theme } from "./themes.js";
 
 const registeredMimeTypes = new Set<string>();
 const unsupportedMimeTypes = new Set<string>();