How to get the active reader when a PDF file is opened in a separate window?

[taquangtrung]

Hi,

When open a PDF file as a tab of the main Zotero pane, I can get the PDF reader by this script:

const Zotero = require("Zotero");
const Zotero_Tabs = require("Zotero_Tabs");
let reader = Zotero.Reader.getByTabID(Zotero_Tabs.selectedID);

However, the above script doesn't work when the PDF file is opened in a separate window.
Does anyone know how to get the reader in such a case?

Thank you!