Can't modify state in module context

[michielp1807]

Describe the bug

If we define some $state in a module script, then attempts to modify that state will lead to a vague "module.end is null" error in Firefox, or a vague "Cannot read properties of null (reading 'line')" error in Chrome.

Reproduction

• Pushing to an array
• Modifying an object

Note that with simple state types, such as just a number or a string, it does work fine without problems.

Logs

No response

System Info

System:
    OS: Linux 5.15 Ubuntu 20.04.6 LTS (Focal Fossa)
    CPU: (4) x64 AMD Ryzen 3 3200G with Radeon Vega Graphics
    Memory: 6.45 GB / 15.54 GB
    Container: Yes
    Shell: 5.0.17 - /bin/bash
  Binaries:
    Node: 22.11.0 - ~/.nvm/versions/node/v22.11.0/bin/node
    npm: 10.9.0 - ~/.nvm/versions/node/v22.11.0/bin/npm
  Browsers:
    Chromium: 130.0.6723.91
  npmPackages:
    svelte: ^5.0.0 => 5.1.13

Severity

annoyance