I agree, this is still happening to myself and my wife.
If we use the red stop button to close Orion, we lose all our tabs when we re-open. But if we use command + q or quit from the Orion dropdown menu, our tabs are restored when we re-open.
Both of us are on Mac using Sonoma 14.3.1 Orion Plus Version 0.99.126.4.1-beta (WebKit 618.1.2)
Thank you