diff --git a/packages/node_modules/@node-red/editor-client/src/vendor/monaco/monaco-bootstrap.js b/packages/node_modules/@node-red/editor-client/src/vendor/monaco/monaco-bootstrap.js
index 2c66859c2..7147ae0e7 100644
--- a/packages/node_modules/@node-red/editor-client/src/vendor/monaco/monaco-bootstrap.js
+++ b/packages/node_modules/@node-red/editor-client/src/vendor/monaco/monaco-bootstrap.js
@@ -1,26 +1,48 @@
-(function() {
-    var _isIE = /MSIE \d|Trident.*rv:/.test(navigator.userAgent);
-    //dont load monaco if IE
-    if(_isIE === false) {
-        var userLocale = (localStorage.getItem("editor-language") + "")
-        var browserLocale = typeof navigator === "undefined" ? "" : (navigator.language ||  navigator.userLanguage || "");
-        var cultureDists = {
-            "zh-cn":"zh-hans",
-            "zh-tw":"zh-hant",
-            "ja":"ja",
-            "ko":"ko",
-            "de":"de",
-            "fr":"fr",
-            "it":"it",
-            "es":"es",
-            "ru":"ru",
-            "tr":"tr",
-            "pl":"pl",
-            "pt-br":"pt-br",
-            "cs":"cs"
-        };
-        var uiLanguage = cultureDists[userLocale.toLowerCase()] || cultureDists[browserLocale.toLowerCase()];
-        if(uiLanguage) document.write('<script src="vendor/monaco/dist/locale/' + uiLanguage + '.js"><\/script>'); 
-        document.write('<script src="vendor/monaco/dist/editor.js"><\/script>');
+(function () {
+    // Supported/built-in Monaco locales as of v0.55.1
+    // NOTES:
+    //  - 'en' is built-in (not a lang pack) so will not actually be loaded.
+    //  - 'es-es' is a listed language in the NR Language dropdown, however in the case where a user has set their
+    //    locale to 'es-mx' (or other spanish variant) we will default to 'es' in the getCultureDist helper function.
+    //  - 'zh-hans' & 'zh-hant' are not listed in the NR Language dropdown, but they are valid BCP 47 Chinese lanuages that
+    //    monaco supports. If the users navigator.language is set to one of these, we allow it since it is a monaco supported language.
+    //  - 'it', 'pl' and 'tr' are not listed in the NR Language dropdown, however they are supported by monaco, so we allow
+    //    that lang pack to be loaded when the user has set their browser locale to one of those languages.
+    const langPacks = {
+        'en': 'BUILT-IN',
+        'cs': 'cs.js',
+        'de': 'de.js',
+        'es-es': 'es.js',
+        'es': 'es.js', // fallback for other spanish variants such as es-mx. See notes above.
+        'fr': 'fr.js',
+        'it': 'it.js',
+        'ja': 'ja.js',
+        'ko': 'ko.js',
+        'pl': 'pl.js',
+        'pt-br': 'pt-br.js',
+        'ru': 'ru.js',
+        'tr': 'tr.js',
+        'zh-cn': 'zh-cn.js',
+        'zh-hans': 'zh-hans.js', // See notes above
+        'zh-hant': 'zh-hant.js', // See notes above
+        'zh-tw': 'zh-tw.js',
     }
-})();
\ No newline at end of file
+    // Determine the UI language - first try full BCP 47 user setting, then its base language, then browser prefered language(s).
+    const userLocale = (localStorage.getItem('editor-language') || '').toLowerCase()
+    let langPack = langPacks[userLocale] || langPacks[userLocale.split('-')[0]] // try full locale, then base language
+    if (!langPack && window.navigator) {
+        const languages = navigator.languages || [navigator.language]
+        for (let i = 0; i < languages.length; i++) {
+            const lang = (languages[i] || '').toLowerCase()
+            langPack = langPacks[lang] || langPacks[lang.split('-')[0]] // try full locale, then base language
+            if (langPack) { break }
+        }
+    }
+
+    // If we have a suitable language pack, add a script tag to load it (note 'en' is built-in)
+    if (langPack && langPack !== 'BUILT-IN') {
+        document.write('<script src="vendor/monaco/dist/locale/' + langPack + '"><\/script>')
+    }
+    document.write('<script src="vendor/monaco/dist/editor.js"><\/script>')
+
+})();