HTML5 validity popups not appearing

[howardb]

If you have the following html code: <input id="searchFormId" required="" type="number" min="9200000000000000" max="9299999999999999" name="id" class="form-control" placeholder="card" oninvalid="setCustomValidity('Card number must be 16 digits long and start with 92')"> then when you enter an invalid number (eg 6) and click off the field, the oninvalid should trigger and show a popup with the error message. This works well in Chrome. Nothing happens in Vivaldi. This should be an internal browser popup of some form. Not sure if some of the other html5 validation is properly showing internal browser errors either - e.g. pattern..? Not sure if this is Windows specific - I don't have any other o/s to test on, sorry!