Path argument with ? become %3F

Hi,
for my application, when creating my mainWindow, it opens a file and take argument from it. Then it must launch an html in Electron app with this argument.

var fileSettings = "./Blockly@rduino.json";
var Settings = fs.readFileSync(fileSettings, 'utf8', (err, Settings) => {
                        if (err) {
                            console.log("An error occured reading the file :" + err.message);
                            return
                        }
                        console.log("The file Settings is : " + Settings);
                })
mainWindow.loadURL(path.join(__dirname, '/www/index_electron.html' + Settings));

Inside my fileSettings Blockly@rduino.json there is just: β€œ?font=O&lang=en”

Electron app launches but cannot open index_electron.html, in console I can read:
Not allowed to load local resource: file:///F:/Logiciels/BlocklyArduino_AIO/www/index_electron.html%3Ffont=O&lang=en

So the problem is about the β€˜?’ encoding, but I searched for hours on the web without no ideas how to resolve it. And it worked with older version of Electron.
Electron Version:
8.2.5
Operating System:
Windows 7 Pro x64
Last Known Working Electron version:
4.1.1

Many thanks.