The intro that hid the page

On vandatateam.com an intro overlay held the home page for three to six seconds on desktop. During hydration it was unmounted and mounted again, so the page flashed into view and was then covered a second time.

Removing the intro was the small part. It had been covering other problems. A WebGL scene ran on the main thread, and the client bundles shipped the whole blog to every visitor. The scene moved into a Web Worker with OffscreenCanvas, and the blog copy now stays on the server.

To compare before and after, I ran both builds as production servers on the same machine, back to back in alternating order, so background load hit both equally. The top of the page became visible on desktop in 526 ms instead of 4,493 ms.

This site had a curtain of its own between pages until November 2026. I took it out for the same reason.