details

object.

tabId

integer. The ID of the tab whose title you want to set.

title

string or null. The tooltip text.

If null is passed here, the title is reset to the title that was specified in the page_action manifest key.

Whenever a tab is updated, show the page action for that tab, and set its title to show the tab's ID:

browser.tabs.onUpdated.addListener((tabId, changeInfo, tabInfo) => {
  browser.pageAction.show(tabId);
  browser.pageAction.setTitle({
    tabId,
    title: `Tab ID: ${tabId}`,
  });
});

• apply-css