Vue SPA briefly shows the default before the variant appears

My app is a client-rendered Vue SPA built with Vite. When a page loads, users see the default hero for a moment and then the personalized variant swaps in on top of it. It is a short flash but it is noticeable, especially on slower connections.

I do not have a server render in this setup, everything happens in the browser. Is this flash even avoidable given that constraint, or is it just the price of a pure SPA