diff --git a/testsuite/tests/util/Styles.test.ts b/testsuite/tests/util/Styles.test.ts
index 34c097b97..1c5cdc381 100644
--- a/testsuite/tests/util/Styles.test.ts
+++ b/testsuite/tests/util/Styles.test.ts
@@ -439,6 +439,9 @@ describe('CssStyles object', () => {
       'font-family': 'arial',
       'font-style': 'italic'
     });
+    cssFontTest('font-size-adjust: none', {
+      'font-size-adjust': 'none',
+    });
   });
 
   test('get()', () => {
diff --git a/ts/util/Styles.ts b/ts/util/Styles.ts
index 8290f0dfd..e7eff21f9 100644
--- a/ts/util/Styles.ts
+++ b/ts/util/Styles.ts
@@ -157,6 +157,7 @@ function splitSame(name: string) {
  * @param {string} name   The style to be processed
  */
 function combineSame(name: string) {
+  if (!Styles.connect[name]) return;
   const children = [...Styles.connect[name].children];
   const value = this.styles[this.childName(name, children.shift())];
   for (const child of children) {