one.js

import Rails from '@rails/ujs'

three.js

Rails.ajax({
    url: `http://SERVER_URL/tasks/${task.id}`
    type: 'PATCH',
    data: data,
    dataType: 'JSON',
});

two-second.js

const data = new FormData();
data.append('task[assignee_id]', this.someUserId || '');
data.append('task[name]', this.taskName || '');

two.js

const data = new FormData();
data.append('task[assignee_id]', this.someUserId);
data.append('task[name]', this.taskName);