[VSCode] Fix syntax highlighting

Fixes #2969

1 files changed, 3 insertions, 1 deletions

diff --git a/editors/code/src/color_theme.ts b/editors/code/src/color_theme.ts
index cbad47f35..e4d20490b 100644
--- a/editors/code/src/color_theme.ts
+++ b/editors/code/src/color_theme.ts
@@ -28,7 +28,9 @@ export class ColorTheme {
     static fromRules(rules: TextMateRule[]): ColorTheme {
         const res = new ColorTheme();
         for (const rule of rules) {
-            const scopes = typeof rule.scope === 'string'
+            const scopes = typeof rule.scope === 'undefined'
+                ? []
+                : typeof rule.scope === 'string'
                 ? [rule.scope]
                 : rule.scope;
             for (const scope of scopes) {