unnamed tab codeblocks cause flickering on the client

[bigmistqke]

Codeblocks with a tab-directive flicker when they appear on screen.
The error is not present when the tab directive has a name: tab="some-id", only with unnamed tabs.

Minimal reproduction

These snippets come from the ec.mdx in dev-directory. The bug is also visible https://solidbase.dev/guide/features/markdown/

This will cause a flickering:

``tsx {4} tab title="a.tsx"
import { SolidBaseApp } from "@kobalte/solidbase";

export default function App() {
  return <SolidBaseApp a />;
}
``

``tsx {4} tab title="b.tsx"
import { SolidBaseApp } from "@kobalte/solidbase";

export default function App() {
  return <SolidBaseApp b />;
}
``

This causes no flickering:

``tsx {4} tab="key" title="a.tsx"
key
import { SolidBaseApp } from "@kobalte/solidbase";

export default function App() {
  return <SolidBaseApp a />;
}
``

``tsx {4} tab="key" title="b.tsx"
import { SolidBaseApp } from "@kobalte/solidbase";

export default function App() {
  return <SolidBaseApp b />;
}
``

(codeblocks only have double backticks so i can render it in a codeblock)

Screen recording

Screen.Recording.2025-10-29.at.13.14.59.mov

Screen shots

Initially tabpanel is not rendered

After hydration it pops into place

I initially thought they would be client rendered, but it does seem like it receives the correct attributes:

If I run the snippet with javascript disabled, the unnamed tab never become visible:

Screen.Recording.2025-10-29.at.13.23.11.mov

but it does look like the html is already present.