in src/auth/AccessTokenHelpers.ts [44:52]
public static generateCodeVerifier(length: number) {
let text = '';
let possible = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
for (let i = 0; i < length; i++) {
text += possible.charAt(Math.floor(Math.random() * possible.length));
}
return text;
}