in packages/rum-core/src/common/config-service.js [142:156]
setUserContext(userContext = {}) {
const context = {}
const { id, username, email } = userContext
if (typeof id === 'number' || typeof id === 'string') {
context.id = id
}
if (typeof username === 'string') {
context.username = username
}
if (typeof email === 'string') {
context.email = email
}
this.config.context.user = extend(this.config.context.user || {}, context)
}