diff --git a/apps/client/src/translations/en/translation.json b/apps/client/src/translations/en/translation.json
index aa8c5926c..d1f70699f 100644
--- a/apps/client/src/translations/en/translation.json
+++ b/apps/client/src/translations/en/translation.json
@@ -1309,7 +1309,10 @@
     "title": "Editor"
   },
   "code_mime_types": {
-    "title": "Available MIME types in the dropdown"
+    "title": "Available MIME types in the dropdown",
+    "tooltip_syntax_highlighting": "Syntax highlighting",
+    "tooltip_code_block_syntax": "Code blocks in Text notes",
+    "tooltip_code_note_syntax": "Code notes"
   },
   "vim_key_bindings": {
     "use_vim_keybindings_in_code_notes": "Vim keybindings",
diff --git a/apps/client/src/widgets/type_widgets/options/code_notes.tsx b/apps/client/src/widgets/type_widgets/options/code_notes.tsx
index e2a046cd7..7d69cc1cb 100644
--- a/apps/client/src/widgets/type_widgets/options/code_notes.tsx
+++ b/apps/client/src/widgets/type_widgets/options/code_notes.tsx
@@ -4,7 +4,7 @@ import Column from "../../react/Column";
 import FormCheckbox from "../../react/FormCheckbox";
 import FormGroup from "../../react/FormGroup";
 import FormSelect from "../../react/FormSelect";
-import { useTriliumOption, useTriliumOptionBool, useTriliumOptionJson } from "../../react/hooks";
+import { useStaticTooltip, useTriliumOption, useTriliumOptionBool, useTriliumOptionJson } from "../../react/hooks";
 import OptionsSection from "./components/OptionsSection";
 import { useEffect, useMemo, useRef } from "preact/hooks";
 import codeNoteSample from "./samples/code_note.txt?raw";
@@ -14,6 +14,8 @@ import mime_types from "../../../services/mime_types";
 import CheckboxList from "./components/CheckboxList";
 import AutoReadOnlySize from "./components/AutoReadOnlySize";
 import "./code_notes.css";
+import { byMimeType as codeBlockMimeTypes } from "@triliumnext/highlightjs/src/syntax_highlighting";
+import { default as codeNoteMimeTypes } from "@triliumnext/codemirror/src/syntax_highlighting";
 
 const SAMPLE_MIME = "application/typescript";
 
@@ -134,6 +136,26 @@ function CodeMimeTypes() {
 type MimeTypeWithDisabled = MimeType & { disabled?: boolean };
 
 export function CodeMimeTypesList() {
+    const containerRef = useRef<HTMLUListElement>(null);
+    useStaticTooltip(containerRef, {
+        title() {
+            const mime = this.querySelector("input")?.value;
+            if (!mime) return "";
+
+            const hasCodeBlockSyntax = !!codeBlockMimeTypes[mime];
+            const hasCodeNoteSyntax = !!codeNoteMimeTypes[mime];
+
+            return `
+                <strong>${t("code_mime_types.tooltip_syntax_highlighting")}</strong><br/>
+                ${hasCodeBlockSyntax ? "✅" : "❌"} ${t("code_mime_types.tooltip_code_block_syntax")}<br/>
+                ${hasCodeNoteSyntax ? "✅" : "❌"} ${t("code_mime_types.tooltip_code_note_syntax")}
+            `;
+        },
+        selector: "label",
+        placement: "right",
+        fallbackPlacements: [ "left", "right" ],
+        html: true
+    });
     const [ codeNotesMimeTypes, setCodeNotesMimeTypes ] = useTriliumOptionJson<string[]>("codeNotesMimeTypes");
     const groupedMimeTypes: Record<string, MimeType[]> = useMemo(() => {
         mime_types.loadMimeTypes();
@@ -160,7 +182,7 @@ export function CodeMimeTypesList() {
     }, [ codeNotesMimeTypes ]);
 
     return (
-        <ul class="options-mime-types">
+        <ul class="options-mime-types" ref={containerRef}>
             {Object.entries(groupedMimeTypes).map(([ initial, mimeTypes ]) => (
                 <section>
                     { initial && <h5>{initial}</h5> }
diff --git a/packages/highlightjs/src/syntax_highlighting.ts b/packages/highlightjs/src/syntax_highlighting.ts
index dc94d6303..1970e1b40 100644
--- a/packages/highlightjs/src/syntax_highlighting.ts
+++ b/packages/highlightjs/src/syntax_highlighting.ts
@@ -3,7 +3,7 @@ import type { LanguageFn } from "highlight.js";
 
 type MimeRecord = Record<string, (() => Promise<{ default: LanguageFn}>) | null>;
 
-const byMimeType: MimeRecord = {
+export const byMimeType: MimeRecord = {
     "text/plain": () => import("highlight.js/lib/languages/plaintext"),
     "application/dart": () => import("highlight.js/lib/languages/dart"),
     "application/edn": () => import("highlight.js/lib/languages/clojure"),