Use Session cookies?

Love the plugin! I see via Chrome Dev tools it creates a regular, preference cookie to store the currency (e.g. EUR) with an expiry date. Could the plugin code be modified slightly to use Session cookies instead, which expire when the browser is closed?

The reason: I believe the (accursed) GDPR permits preference *session* cookies without having to display a cookie notice. Regular cookies – with an expiry date – do require a cookie notice, alas.

Many thanks! Duncan