CSS - Class not applied to child elements

[ghost]

Linux Mint 18.3 Cinnamon
Google Chrome Version 65.0.3325.146 (Official Build) (64-bit)
Firefox Quantum 58.0.2 (64-bit)
svelte: ^1.57.1

Svelte REPL gist

<!-- DevTools Inspector -->
<div class="cl1 svelte-1rs9q0o">
    Test 
    <div class="cl2">Test 2</div> <!-- class svelte-1rs9q0o missing from element, if added in DevTools it works -->
</div>

If I add {{anyTag}} inside any div, regardless of the depth, then svelte-1rs9q0o is present and styles are applied.
I've tried with depth of 3 and 4. Same behavior.

[Rich-Harris]

fixed in 1.57.3, thanks!

[ghost]

You're Welcome!
I know you’ll do that for someone else! ;)