var scripts = document.querySelectorAll('head script:not([src])');
var odooDebugInfo = false;
scripts.forEach(function(script) {
    var scriptText = script.text;
    if (scriptText.trim().startsWith("var odoo =")) {
        // For odoo < v11
        console.log(window.location);
        // For odoo > v12
        if (scriptText.includes("debug:")) {
            eval(scriptText);
            odooDebugInfo = odoo;
        }
    }
});

console.log(odooDebugInfo); // for v12