Add custom active links to customer account navigation in Magento 2

To get the things done, please change the path in your layout file like below.

<argument name="path" xsi:type="string">support/customer</argument>

Please note, i have removed action part from the path string.

For more information, why you need to do this please study below file.

Magento\Framework\View\Element\Html\Link\Current.php

Hope, this will help you.

You can write in your custom layout

<referenceBlock name="customer-account-navigation-suppport-ticket-link">
                <arguments>
                    <argument name="current" xsi:type="boolean">true</argument>
                </arguments>
    </referenceBlock>