diff --git a/src/editor/annotation.js b/src/editor/annotation.js
index 09342c2..5e46be7 100644
--- a/src/editor/annotation.js
+++ b/src/editor/annotation.js
@@ -9,3 +9,9 @@ export const DELETE_BLOCK = "heynote-delete-block"
 export const CURSOR_CHANGE = "heynote-cursor-change"
 export const APPEND_BLOCK = "heynote-append-block"
 export const SET_FONT = "heynote-set-font"
+
+
+// This function checks if any of the transactions has the given Heynote annotation
+export function transactionsHasAnnotation(transactions, annotation) {
+    return transactions.some(tr => tr.annotation(heynoteEvent) === annotation)
+}
diff --git a/src/editor/block/math.js b/src/editor/block/math.js
index b76a73f..4de7061 100644
--- a/src/editor/block/math.js
+++ b/src/editor/block/math.js
@@ -4,7 +4,7 @@ import { RangeSetBuilder } from "@codemirror/state"
 import { WidgetType } from "@codemirror/view"
 
 import { getNoteBlockFromPos } from "./block"
-import { CURRENCIES_LOADED } from "../annotation"
+import { transactionsHasAnnotation, CURRENCIES_LOADED } from "../annotation"
 
 
 class MathResult extends WidgetType {
@@ -107,12 +107,6 @@ function mathDeco(view) {
     return builder.finish()
 }
 
-
-// This function checks if any of the transactions has the given annotation
-const transactionsHasAnnotation = (transactions, annotation) => {
-    return transactions.some(tr => tr.annotations.some(a => a.value === annotation))
-}
-
 export const mathBlock = ViewPlugin.fromClass(class {
     decorations
 
diff --git a/src/editor/todo-checkbox.ts b/src/editor/todo-checkbox.ts
index 60d76a6..a25a1ee 100644
--- a/src/editor/todo-checkbox.ts
+++ b/src/editor/todo-checkbox.ts
@@ -4,7 +4,7 @@ import { WidgetType } from "@codemirror/view"
 import { ViewUpdate, ViewPlugin, DecorationSet } from "@codemirror/view"
 
 import { isMonospaceFont } from "./theme/font-theme"
-import { SET_FONT } from "./annotation"
+import { transactionsHasAnnotation, SET_FONT } from "./annotation"
 
 
 class CheckboxWidget extends WidgetType {
@@ -111,7 +111,7 @@ export const todoCheckboxPlugin = [
         }
 
         update(update: ViewUpdate) {
-            if (update.docChanged || update.viewportChanged || update.transactions.some(tr => tr.annotations.some(a => a.value === SET_FONT))) {
+            if (update.docChanged || update.viewportChanged || transactionsHasAnnotation(update.transactions, SET_FONT)) {
                 this.decorations = checkboxes(update.view)
             }
         }