Is the bonus an employee received permissible or forbidden, knowing that he could have refused it and that it was given in exchange for extra work requested by the manager?

It is permissible for an employee to accept a bonus from their manager for work performed during working hours if this work serves the company's interest and the manager is authorized to request it. However, if the work is for the manager's personal interest, the employee is not permitted to obey, because the employee's time during working hours belongs to the employer.

If the manager is authorized to dispose of the employee's time and assign them personal tasks, then there is no harm in obeying them and accepting a bonus from them, provided that the bonus is from the manager's personal funds or that the manager is authorized to disburse bonuses from the employer.

If the manager is not authorized, then both the manager and the employee are sinful for infringing upon the company's rights. In this case, the bonus is forbidden, and the employee must spend it on general Muslim welfare or give it to the poor.