browser.pageAction.onClicked.addListener(listener)
browser.pageAction.onClicked.removeListener(listener)
browser.pageAction.onClicked.hasListener(listener)

Events have three functions:

addListener(callback)

Adds a listener to this event.

removeListener(listener)

Stop listening to this event. The listener argument is the listener to remove.

hasListener(listener)

Checks whether a listener is registered for this event. Returns true if it is listening, false otherwise.

callback

A function that will be called when this event occurs. The function is passed the following arguments:

tab

A tabs.Tab object representing the tab whose page action was clicked.

OnClickData

An object containing information about the click.

modifiers

An array. The keyboard modifiers active at the time of the click, being one or more of Shift, Alt, Command, Ctrl, or MacCtrl.

button

An integer. Indicates the button used to click the page action icon: 0 for a left-click or a click not associated with a mouse, such as one from the keyboard and 1 for a middle button or wheel click. Note that the right-click is not supported because Firefox consumes that click to display the context menu before this event is triggered.

When the user clicks the page action, hide it, and navigate the active tab to "https://giphy.com/explore/cat":

let CATGIFS = "https://giphy.com/explore/cat";

browser.pageAction.onClicked.addListener((tab) => {
  browser.pageAction.hide(tab.id);
  browser.tabs.update({url: CATGIFS});
});

browser.pageAction.onClicked.addListener(() => {
});

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