bug #5245 Fix issue #5212 - frontend validation hits disabled element…

…s (=)

This PR was merged into the 4.x branch.

Discussion
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Fix issue #5212 - frontend validation hits disabled elements

Note: background style problem mentioned in the issue is not covered

Commits
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8d4fd16 Fix issue #5212

assets/js/form.js

@@ -65,7 +65,7 @@ class Form {
                     });
 
                     form.querySelectorAll('input,select,textarea').forEach( (input) => {
-                        if (!input.validity.valid) {
+                        if (!input.disabled && !input.validity.valid) {
                             formHasErrors = true;
 
                             // Visual feedback for tabs