When someones sees an out of stock product, there is the option to fill out an email field to get notified of re-stock. However no matter what email format is used, they always get "Invalid Email" message displayed. 

I see nothing wrong with the related view "product_wishlist" 

     </div>

                    <div id="stock_notification_form" class="d-none">

                        <div class="input-group">

                            <input id="stock_notification_input" class="form-control" name="email" type="text" placeholder="votremail@gmail.com" t-att-value="request.env.user.partner_id.email or request.session.get('stock_notification_email', '')"/>

                            <div id="wishlist_stock_notification_form_submit_button" class="btn btn-secondary">

                                <i class="fa fa-paper-plane"/>

                            </div>

                            <div id="stock_notification_input_incorrect" class="btn d-none">

                                <i class="fa fa-times text-danger"/>

                                Invalid email

                            </div>

                        </div>

                    </div>

                    <div id="stock_notification_success_message" class="text-muted" t-att-class="'text-muted' if has_stock_notification else 'd-none'">

                        <i class="fa fa-bell"/>

                        We'll notify you once the product is back in stock.

                    </div>

I'm on a custom OVH mail server. Is it related ? 

Many thanks