Chrome Extension how to insert text?

Question

JavaScript

I'm trying to write an Extension for Chrome. Created a context menu. How can I insert text into a textarea when clicking on a menu?

function addText (info, tab) {
        console.log(info, tab);
}
chrome.contextMenus.create({
            'contexts': ['editable'],
            'onclick': addText
});

Answer 1

As I understand it, the context menu will be called only on this very textarea. Then you can write something like this, remembering the element on which the right click occurred.
1. content.js

var AppContent = {
    init: function() {
        document.body.addEventListener("contextmenu", function(event) {
            chrome.runtime.sendMessage({action: "rememberTarget", data: event.target});
        });
    }
};
AppContent.init();

2. background.js

var AppBackground = {
    target: null,
    init: function() {
        chrome.runtime.onMessage.addListener(function(request) {
            if(request.action === "rememberTarget")
                this.target = request.data;
        }.bind(this));
        
        chrome.contextMenus.create({
            'contexts': ['editable'],
            'onclick': function() {
                if(this.target)
                    this.target.value = "some text";
            }.bind(this)
        });
    }
}
AppBackground.init();