End to End Encryption on Browsers

I have only noticed 2 Facebook friends so far with this recent end to end encryption. I am not able to chat with them at all now. As soon as I close my browser any conversation that is there post end to end encryption is wiped out. I recently discovered this is happening because I have my browser set to wipe out cookies when I close my browser. That's what I prefer. Doe's Meta honestly expect people to not clean their browsers out every now and then? Isn't that something that is recommended in general? Who does Meta think they are? They just want so badly to have their cookies on our devices. Is that the ulterior motive here? Is their a work around yet so I can continue using messenger on my browser?