Render context menu depending on selection

I want to display a different menu option depending on whether a number or text is selected.

I've tried playing with content scripts but I can't get them to work in gmail which is where I need it to work. Here is what I have, it works on sites other than开发者_运维技巧 gmail (is it a https thing?)

Background.html

<script src="driver.js"></script>

content_script.js

document.addEventListener("mousedown", function(event){
  if(event.button == 2) {
    var selection = window.getSelection().toString();
    chrome.extension.sendRequest({cmd: selection});
  }

}, true);

driver.js

chrome.extension.onRequest.addListener(function(request) {
    alert(request.cmd);
});

manifest.json

{
"name": "Context Menu Search",
"description": "Opens the selected text as keyword in a new window",
"version": "0.1",
"permissions": ["contextMenus"],
  "content_scripts": [
    {
      "matches": ["http://*/*","https://*/*"],
      "js": ["content_script.js"]
    }
  ],
"background_page": "background.html"
}

---

Selection type changes context menu using chrome extension

You will have to set a listener for mouse down. There is no other way to get the selected text before the menu is created.

See this SO question:

chrome extension context menus, how to display a menu item only when there is no selection?

Here is part of the code the rest is at the link.

document.addEventListener("mousedown", function(event){
//right click
if(event.button == 2) {
    if(window.getSelection().toString()) {
        chrome.extension.sendRequest({cmd: "createSelectionMenu"});
    } else {
        chrome.extension.sendRequest({cmd: "createRegularMenu"});
    }
   }
}, true);