Every extension has an ID and, when installed, a manifest that stays on the user’s computer.
Just go to the following address:
chrome-extension://ID/manifest.json
<!-- Substitua o "ID" acima pelo da sua aplicação. -->
<!-- Note que ID é um texto bem longo e aleatório, não um número. -->
You can do this with ajax, for example. If error 404 is because the extension is not installed.
A very simple attempt to access the address via Ajax can be made like this:
$.ajax({
url: "chrome-extension://idnljhnpjegfbcohjhdnhjlnfnffmbnf/manifest.json"
// A extensão acima é o módulo de proteção do Santander.
});
Since you are the author of your extension, it is up to you to determine your ID. To test this with extensions you haven’t developed, I’ll leave you a hint: go to settings -> extensions and look for the Id’s of the extensions in the source code of the page ;) Then just use the above form to test with the extensions you already have on your machine.
To be able to access via ajax the features of the extension you need to give access to the file in the manifest: "web_accessible_resources": [ "manifest.json" ],
– user3092202