https://github.com/magento/magento2/issues/35286
https://alexanderell.is/posts/typeof-null/
@DO - In Firefox at least...when value is null

--- a/vendor/magento/module-page-builder/view/adminhtml/web/js/form/element/validator-rules-mixin.js
+++ b/vendor/magento/module-page-builder/view/adminhtml/web/js/form/element/validator-rules-mixin.js
@@ -234,7 +234,7 @@
                 var allFilled;

                 // Validation only for margins and paddings
-                if (typeof value === 'object' && !!(value.padding || value.margin)) {
+                if (typeof value === 'object' && value !== null && !!(value.padding || value.margin)) {
                     allFilled = true;

                     _.flatten(_.map(value, _.values)).forEach(function (val) {