Poor performance on tw4 branch vs tw3

[alexandersmpx]

Describe the bug

Hi, we noticed a big performance hit on tw4 branch vs tw3 branch. Tw3 branch was very responsive but latest shadcn-svelte has a lot of lag spikes on data tables, select components.

Happens in Chrome but not Firefox.

Here is a video of the issue (notice the spikes in performance tab)

https://cdn.discordapp.com/attachments/1494717625312477386/1494717626771964114/2026-04-17_11-10-39.mp4?ex=69e39fc4&is=69e24e44&hm=7231e833eee3b64263d14f70bed4238dc24c24a672a35a584c0d9039c9c00b82&

Reproduction

Open https://www.shadcn-svelte.com/docs/components/data-table in Chrome and click on Columns dropdown

Logs

System Info

System:
    OS: Windows 10 10.0.19045
    CPU: (8) x64 Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz
    Memory: 14.15 GB / 31.94 GB
  Binaries:
    Node: 22.19.0 - C:\Program Files\nodejs\node.EXE
    Yarn: 1.22.22 - C:\Program Files\nodejs\yarn.CMD
    npm: 11.12.0 - C:\Program Files\nodejs\npm.CMD
    pnpm: 10.8.0 - C:\Users\User\AppData\Local\pnpm\pnpm.CMD
  Browsers:
    Chrome: 147.0.7727.57
    Edge: Chromium (140.0.3485.54)
    Firefox: 145.0.2 - C:\Program Files\Mozilla Firefox\firefox.exe
    Internet Explorer: 11.0.19041.5794
  npmPackages:
    @lucide/svelte: ^1.8.0 => 1.8.0
    @sveltejs/kit: ^2.0.0 => 2.55.0
    bits-ui: ^2.17.3 => 2.17.3
    formsnap: ^2.0.1 => 2.0.1
    mode-watcher: ^1.1.0 => 1.1.0
    shadcn-svelte: ^1.2.7 => 1.2.7
    svelte: ^5.0.0 => 5.55.0
    svelte-radix: ^2.0.1 => 2.0.2
    svelte-sonner: ^1.1.0 => 1.1.0
    sveltekit-superforms: ^2.30.1 => 2.30.1
    tailwindcss: ^4.2.2 => 4.2.2
    vaul-svelte: ^1.0.0-next.7 => 1.0.0-next.7

Severity

annoyance

[ieedan]

Is this on installed components or just the docs?

[alexandersmpx]

Is this on installed components or just the docs?

It happens on installed components as well in our project. I just picked the docs for the ease of reproduction.

[ieedan]

I'm not really aware of anything specific that would be causing this in installed components since they should have the same internals. But if you can provide a reproduction we can definitely take a look!

[github-actions]

Please provide a reproduction.

More info

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You might also find these other articles interesting and/or helpful:

• The Importance of Reproductions
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[alexandersmpx]

I'm not really aware of anything specific that would be causing this in installed components since they should have the same internals. But if you can provide a reproduction we can definitely take a look!

Okay I will try to make a repro. Do you also notice the slowdown on Chrome in original shadcn website?
https://ui.shadcn.com/docs/components/radix/data-table

If you click on "Columns"

[ieedan]

With the way the icon libraries work we have to load icons every time we open that menu so that would likely account for that slowdown. Again probably not a thing once you actually install the components into your project.

[alexandersmpx]

With the way the icon libraries work we have to load icons every time we open that menu so that would likely account for that slowdown. Again probably not a thing once you actually install the components into your project.

Yea I saw you pointing this out earlier in #2584

But I don't think it's the same. I will make a repro. Thanks

[The-LukeZ]

I got the same issue actually

[phi-friday]

Removing supports-backdrop-filter:backdrop-blur-xs from the dialog-overlay component prevents the performance issue in Chrome.

I've temporarily removed that class and changed bg-black/10 to bg-black/30. It would be great if there's a solution.