Is he who sees lewd images – without intending to see them – while browsing the internet to get a program that is not essential, sinful?

A Muslim is exposed to trials (fitan), and hearts are affected by them. If a heart absorbs a trial, a black spot is made in it. If it rejects it, a white spot is made in it. Therefore, we hope that the questioner is not sinful for what he mentioned. It is better for him not to enter unnecessary websites that contain trials, and to be content with safe websites that achieve his purpose and happiness in his religion and his worldly life.