Hello,
First, we have no control over Puffin or how they develop their software or what they do that negatively impacts this game. This is why the game now negatively interacts with Chrome and Firefox in so many ways. It was not the game that changed; it was Chrome and Firefox. As far as I am aware, there are no plans to change the game to make it less interactable with Puffin.

Second,
Why is puffin the only way you can play the game? I know many people that still play on Chrome and Firefox despite the issues. Some also play on Safari. I myself can log in on Chrome and Firefox, though I prefer miniclient.
Please let me know, thanks!

Ah, I see.
Well, as before, this isn't a game designed to be played on phones, so phone support isn't really extant. There could be phone support in the future, just like how there is mac/ios support being developed now when there was none in the past, but at the present there is not any.
As for Puffin, what they do and how they develop their app is, again, on them. Whether it remains compatible with the game is largely up to them, unfortunately. Puffin is a browser with flash built in, from what I recall, which is what makes it different from the other browsers, and that's why it works for the game when the other browsers have trouble. As to whether that will continue? Again, entirely up to that apps developers. Oasis cannot control that.