Electron preload script for webview not working?

I have this webview that I load like this:

<webview id="link-view"
        src="http://url.espace.com/"
        preload="./preload.js"
        autosize="on"
        partition="persist:link"></webview>

In the preload.js file : I have this

console.log("test");

This doesn't even work..

Can someone explain?