diff --git a/package-lock.json b/package-lock.json
index c4da93bb8cc..f9644ed5537 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -2590,6 +2590,11 @@
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       "integrity": "sha512-a+EPoD+uZiNfh+5fxw2nO9QwFa6nJe2Or35fGY6Ipw1R3R4AGz1d1TEZrCegvw2YTmZ0jXirGYlzxxpYSHwpEg=="
     },
+    "cssesc": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/cssesc/-/cssesc-3.0.0.tgz",
+      "integrity": "sha512-/Tb/JcjK111nNScGob5MNtsntNM1aCNUDipB/TkwZFhyDrrE47SOx/18wF2bbjgc3ZzCSKW1T5nt5EbFoAz/Vg=="
+    },
     "ctags": {
       "version": "3.1.0",
       "resolved": "https://registry.npmjs.org/ctags/-/ctags-3.1.0.tgz",
@@ -3483,11 +3488,6 @@
       "resolved": "https://registry.npmjs.org/flatted/-/flatted-2.0.2.tgz",
       "integrity": "sha512-r5wGx7YeOwNWNlCA0wQ86zKyDLMQr+/RB8xy74M4hTphfmjlijTSSXGuH8rnvKZnfT9i+75zmd8jcKdMR4O6jA=="
     },
-    "flatten": {
-      "version": "1.0.3",
-      "resolved": "https://registry.npmjs.org/flatten/-/flatten-1.0.3.tgz",
-      "integrity": "sha512-dVsPA/UwQ8+2uoFe5GHtiBMu48dWLTdsuEd7CKGlZlD78r1TTWBvDuFaFGKCo/ZfEr95Uk56vZoX86OsHkUeIg=="
-    },
     "focus-trap": {
       "version": "6.1.2",
       "resolved": "https://registry.npmjs.org/focus-trap/-/focus-trap-6.1.2.tgz",
@@ -6086,13 +6086,14 @@
       }
     },
     "postcss-selector-parser": {
-      "version": "2.2.1",
-      "resolved": "https://registry.npmjs.org/postcss-selector-parser/-/postcss-selector-parser-2.2.1.tgz",
-      "integrity": "sha1-/b9pYQOxKwpkBg5WEFB/QQSR98g=",
+      "version": "6.0.4",
+      "resolved": "https://registry.npmjs.org/postcss-selector-parser/-/postcss-selector-parser-6.0.4.tgz",
+      "integrity": "sha512-gjMeXBempyInaBqpp8gODmwZ52WaYsVOsfr4L4lDQ7n3ncD6mEyySiDtgzCT+NYC0mmeOLvtsF8iaEf0YT6dBw==",
       "requires": {
-        "flatten": "^1.0.2",
+        "cssesc": "^3.0.0",
         "indexes-of": "^1.0.1",
-        "uniq": "^1.0.1"
+        "uniq": "^1.0.1",
+        "util-deprecate": "^1.0.2"
       }
     },
     "prebuild-install": {
diff --git a/package.json b/package.json
index 1b443fa0dd7..1408790231c 100644
--- a/package.json
+++ b/package.json
@@ -136,7 +136,7 @@
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     "pathwatcher": "8.1.0",
     "postcss": "8.1.1",
-    "postcss-selector-parser": "2.2.1",
+    "postcss-selector-parser": "6.0.4",
     "prebuild-install": "5.3.5",
     "property-accessors": "^1.1.3",
     "resolve": "1.17.0",