Hello, Looking through https://developer.mozilla.org/en-US/docs/Learn/Forms/Form_validation Firefox supports native HTML5 form validation. In Windows 10 desktop Firefox, trying to submit the form under https://developer.mozilla.org/en-US/docs/Learn/Forms/Form_validation#the_required_attribute without entering anything in the input field would show the message "Please fill out this field" as expected. But testing on Android Firefox mobile 85.1.2 it does not show the error message. Is this a bug? Or known issue or just not a feature for Android Firefox? However, testing on iPhone Firefox, it does show the error message. Thank you.