I think that’s a Safari bug with activeTab, you just have to click twice.

Regardless, with activeTab you can just inject script into the page itself through which you can open a regular popup.

    chrome.scripting.executeScript({
      func: () => window.open(' archive.ph' + location.href)
    })

Currently the extension will suggest that it needs access to every page the user visits, occasionally opening a popup automatically if I remember correctly.

For something that’s a glorified bookmarklet, that’s a lot to ask.