Svelte 5: `<script>` tag doesn't load conditionally

[Aloso]

Describe the bug

An {#if} branch containing only a <script> does not work in Svelte 5; the script isn't loaded when the condition becomes true.

Reproduction

{#if loading}
  <script src="https://www.instagram.com/embed.js"></script>
{/if}

complete reproduction (open the browser console and notice no request is being made)

Somehow it starts working when you add anything else (even whitespace) in the branch:

{#if loading}
  {' '}
  <script src="https://www.instagram.com/embed.js"></script>
{/if}

(it still doesn't work in the svelte playground due to CORS, but the request shows up in the browser console)

Logs

No response

System Info

System:
    OS: Linux 6.7 Manjaro Linux
    CPU: (12) x64 AMD Ryzen 5 5500U with Radeon Graphics
    Memory: 681.68 MB / 7.11 GB
    Container: Yes
    Shell: 5.2.26 - /bin/bash
  Binaries:
    Node: 21.6.2 - /usr/bin/node
    Yarn: 1.22.21 - /usr/bin/yarn
    npm: 10.5.0 - /usr/bin/npm
    pnpm: 8.15.2 - /usr/bin/pnpm
    bun: 0.1.13 - /usr/bin/bun
  Browsers:
    Chromium: 123.0.6312.58
  npmPackages:
    svelte: 5.0.0-next.90 => 5.0.0-next.90

Severity

annoyance