Issue #3467776 by mogtofu33: [1.0.0-alpha3] Form element settings validation

Closes #3467776

css/icon.autocomplete.css

@@ -12,15 +12,21 @@
   margin-block: 0;
 }
 
-.ui-icons-preview {
+/* Keep the settings size close to textfield. */
+.ui-icons-settings-wrapper {
+  max-width: 39rem;
+}
+
+.ui-icons-preview-icon {
+  display: flex;
+  justify-content: center;
+  height: 2.85rem;
   text-align: center;
 }
 
 .ui-icons-preview.form-item {
   min-width: 3rem;
   max-width: 3rem;
-  max-height: 2.65rem;
-  padding: calc(var(--input-padding-vertical) / 3) 0 0 0;
   border: var(--input-border-size) solid var(--input-border-color);
   border-right: 0 none;
   border-top-right-radius: 0;
@@ -28,9 +34,9 @@
   background-color: var(--color-gray-050);
 }
 
-.ui-icons-preview.form-item img,
-.ui-icons-preview.form-item svg {
-  min-width: 2.2rem;
-  max-width: 2.2rem;
-  max-height: 2.2rem;
+.ui-icons-preview-icon img,
+.ui-icons-preview-icon svg {
+  display: block;
+  width: 2.5rem;
+  margin: auto;
 }