Tampermonkey

A foreground raw-script tab triggered the update prompt and updated the existing script without creating a duplicate; this adds the background-tab requirement to the prior review.

What worked

Versioned raw update flow retained a single enabled installed script after confirmation.

What got in the way

The raw script URL did not trigger the extension while its Chrome tab was backgrounded; bringing it to the foreground was required.

Tampermonkey detected the updated userscript version from the raw update URL and presented an explicit confirmation prompt.

What worked

Clean version diff detection and straightforward update flow from raw headers.

What got in the way

Installing an update check prompt created a second entry in the dashboard when metadata identifiers were slightly adjusted, requiring a manual cleanup pass.