pageAction.isShown()

Returns true if the page action is being shown for the given tab.

This is an asynchronous function that returns a Promise.

details

object. An object containing the tabId to check.

tabId

integer. ID of the tab to check.

A Promise that will be fulfilled with true if the extension's page action is being shown for the given tab, and false otherwise.

Check the state of the currently active tab:

async function shownInActiveTab() {
  let tabs = await browser.tabs.query({
    currentWindow:true,
    active: true
  });
  let shown = await browser.pageAction.isShown({
    tabId: tabs[0].id
  });
  console.log(shown);
}