Allow scripts to not register with manifest.json for MV2

[harmonyharmo]

Describe the bug

• should allow scripts to not register with manifest.json for MV2
• It's ok it doesn't use the MV3 specific runtime features

Reproduction

should allow scripts to not register with manifest.json for MV2
It's ok it doesn't use the MV3 specific runtime features

wxt/packages/wxt/src/core/utils/manifest.ts

Line 416 in 30b8ba4

runtimeContentScripts.length > 0 &&

Steps to reproduce

• set registration to runtime in MV2
• Gets error when building

System Info

System:
    OS: Windows 11 10.0.26100
    CPU: (24) x64 13th Gen Intel(R) Core(TM) i7-13700
    Memory: 13.12 GB / 31.77 GB
  Binaries:
    Node: 23.7.0 - ~\scoop\apps\nodejs\current\node.EXE        
    Yarn: 1.22.22 - ~\scoop\apps\yarn\current\bin\yarn.CMD     
    npm: 11.0.0 - ~\scoop\apps\nodejs\current\npm.CMD
    pnpm: 10.3.0 - ~\scoop\shims\pnpm.EXE
    bun: 1.2.2 - ~\scoop\shims\bun.EXE
  Browsers:
    Edge: Chromium (131.0.2903.70)
    Internet Explorer: 11.0.26100.1882

Used Package Manager

bun

Validations

• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
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• The provided reproduction is a minimal reproducible example of the bug.

[aklinker1]

Hmm, well unfortunately I don't remember why I did that lol. Feel free to open a PR to remove that check!

[aklinker1]

In the meantime, you can just use an unlisted script. If you need context, you can just create it:

// entrypoints/my-content-script.content.ts
export default defineUnlistedScript(() => {
  const ctx = new ContentScriptContext("my-content-script");
});

Just make sure the first argument, the entrypoint name, is unique to this script, and no other entrypoints have the same name.

There's nothing magic about the ctx object WXT provides to content scripts, it's just a class, and WXT just constructs it before calling the content script's main function:

wxt/packages/wxt/src/virtual/content-script-isolated-world-entrypoint.ts

Lines 9 to 12 in 151b139

	const { main, ...options } = definition;
	const ctx = new ContentScriptContext(import.meta.env.ENTRYPOINT, options);
	return await main(ctx);