diff --git a/core/.eslintignore b/core/.eslintignore
index 8d687600321..17bb15e4d21 100644
--- a/core/.eslintignore
+++ b/core/.eslintignore
@@ -3,6 +3,7 @@ node_modules/**/*
 **/js_test_files/**/*
 **/build/**/*
 modules/locale/tests/locale_test.js
+misc/jquery.form.js
 
 # Ignore deliberately malformed YAML files.
 modules/system/tests/fixtures/HtaccessTest/access_test.yml
diff --git a/core/.prettierignore b/core/.prettierignore
index fdd0ba31134..bf7ce023193 100644
--- a/core/.prettierignore
+++ b/core/.prettierignore
@@ -2,8 +2,11 @@ assets/vendor/**/*
 node_modules/**/*
 **/build/**/*
 **/js_test_files/**/*
+**/css_test_files/**/*.css
 modules/locale/tests/locale_test.js
 *.yml
+themes/stable9/css/core/assets/vendor/**/*.css
+misc/jquery.form.js
 
 # Temporary until they are brought up to standards
 scripts/**/*
diff --git a/core/misc/jquery.form.js b/core/misc/jquery.form.js
index 335123caf8e..b42ad30437f 100644
--- a/core/misc/jquery.form.js
+++ b/core/misc/jquery.form.js
@@ -21,7 +21,6 @@
  */
 /* global ActiveXObject */
 
-/* eslint-disable */
 (function (factory) {
 	if (typeof define === 'function' && define.amd) {
 		// AMD. Register as an anonymous module.
diff --git a/core/modules/navigation/css/base/variables.css b/core/modules/navigation/css/base/variables.css
index 2d77f9e44f0..e9b918ebe3b 100644
--- a/core/modules/navigation/css/base/variables.css
+++ b/core/modules/navigation/css/base/variables.css
@@ -6,9 +6,10 @@
  */
 /* This is a universal size that helps in the case of themes with a size of 10 pixels.
 We need it root to calculate the size of the displace in .dialog-off-canvas-main-canvas */
+/* prettier-ignore */
 :root {
-  /* stylelint-disable-next-line prettier/prettier */
-  --admin-toolbar-rem: max(1rem, 16px); /* Workaround until postcss-px-to-rem is removed so this is not converted to rems. */
+  /* stylelint-disable-next-line */
+  --admin-toolbar-rem: max(1rem, 16PX); /* Workaround until postcss-px-to-rem is removed so this is not converted to rems. */
 }
 [data-drupal-admin-styles] {
   /*
diff --git a/core/modules/navigation/css/base/variables.pcss.css b/core/modules/navigation/css/base/variables.pcss.css
index eca0e1e8b8c..adc9cb2fc12 100644
--- a/core/modules/navigation/css/base/variables.pcss.css
+++ b/core/modules/navigation/css/base/variables.pcss.css
@@ -2,8 +2,9 @@
 
 /* This is a universal size that helps in the case of themes with a size of 10 pixels.
 We need it root to calculate the size of the displace in .dialog-off-canvas-main-canvas */
+/* prettier-ignore */
 :root {
-  /* stylelint-disable-next-line prettier/prettier */
+  /* stylelint-disable-next-line */
   --admin-toolbar-rem: max(1rem, 16PX); /* Workaround until postcss-px-to-rem is removed so this is not converted to rems. */
 }
 
diff --git a/core/package.json b/core/package.json
index 6b7b9b0c059..76df0045e4a 100644
--- a/core/package.json
+++ b/core/package.json
@@ -19,7 +19,7 @@
     "lint:css-checkstyle": "stylelint \"**/*.css\" --custom-formatter ./node_modules/stylelint-checkstyle-formatter/index.js",
     "lint:yaml": "node ./node_modules/eslint/bin/eslint.js --ext .yml .",
     "test:nightwatch": "node -r dotenv-safe/config ./node_modules/.bin/nightwatch --config ./tests/Drupal/Nightwatch/nightwatch.conf.js",
-    "prettier": "prettier --write \"./**/*.js\"",
+    "prettier": "prettier --write \"./**/*.css\" \"./**/*.js\"",
     "spellcheck": "cspell -c .cspell.json --cache",
     "spellcheck:make-dict": "rm -f misc/cspell/dictionary.txt && touch misc/cspell/dictionary.txt && yarn spellcheck:core --unique --words-only | perl -Mopen=locale -pe '$_=lc$_' | LC_ALL=en_US.UTF-8 tr -d \\\\\\\\ | LC_ALL=C sort -u -o misc/cspell/dictionary.txt",
     "spellcheck:core": "cspell -c .cspell.json --root .. --cache --cache-location core/.cspellcache \"core/**/*\" \"composer/**/*\" \"composer.json\" \".gitlab-ci/*\" \".gitlab-ci.yml\"",