disabled attribute does not disable contenteditable

Phenomenon

The disabled attribute, which disables form inputs, does not work on contenteditable regions in Safari. The contenteditable remains editable and interactive even when disabled is set.

Reproduction example

1. Create a contenteditable div with disabled attribute.
2. Try to focus and edit the content.
3. Observe whether the element is disabled.

Observed behavior

• In Safari on macOS, the disabled attribute does not disable contenteditable.
• The element remains editable and focusable.
• The attribute is ignored.

Expected behavior

• The disabled attribute should disable contenteditable.
• The element should not be editable or focusable when disabled.
• Behavior should match standard input elements.