Content script is incorrectly invalidated when injected multiple times

[namukang]

Describe the bug

When a content script is injected multiple times, all but the most recent one should be invalidated. In practice however, all content scripts, including the most recent one, are invalidated.

Video going over the issue, the root cause, and the fix: https://www.loom.com/share/97983e5d38904af594d5f486bbf9f1f4?sid=e588c652-c868-4cb0-8db2-521650726919

Reproduction

Minimal reproduction: https://github.com/namukang/wxt-invalidation-bug

Steps to reproduce

Steps to reproduce:

1. Clone https://github.com/namukang/wxt-invalidation-bug
2. Run wxt dev
3. Navigate to http://example.com
4. Open the console
5. Click the extension icon

Expected behavior

Only the first content script is invalidated.

Actual behavior

Both content scripts are invalidated.

System Info

System:
    OS: macOS 15.6.1
    CPU: (10) arm64 Apple M1 Max
    Memory: 3.33 GB / 64.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 22.12.0 - /Users/dk/.nvm/versions/node/v22.12.0/bin/node
    npm: 10.9.0 - /Users/dk/.nvm/versions/node/v22.12.0/bin/npm
    pnpm: 10.6.1 - /Users/dk/.nvm/versions/node/v22.12.0/bin/pnpm
    bun: 1.2.23 - /opt/homebrew/bin/bun
    Deno: 2.5.3 - /opt/homebrew/bin/deno
  Browsers:
    Brave Browser: 100.1.37.109
    Chrome: 141.0.7390.107
    Edge: 141.0.3537.71
    Firefox: 133.0.3
    Safari: 18.6
  npmPackages:
    wxt: ^0.20.11 => 0.20.11

Used Package Manager

pnpm

Validations

• [x] Read the Contributing Guidelines.
• [x] Read the docs.
• [x] Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• [x] Check that this is a concrete bug. For Q&A open a GitHub Discussion or join our Discord Chat Server.
• [x] The provided reproduction is a minimal reproducible example of the bug.