Mouse almost auto targeting portal after entering instance

Went to rescue a shippment, the intent was to click on the group to walk, clicked on the corner of the portal, lost a 6M shipping.
Feedback: Woulb be nice, if the portal only showed up when we killed the boss. Maybe it's the MTX of the portal. Not to say never happened to me before. But this accident, came with a big loss of currency, and annoyance.