Is browsing the internet for entertainment during long working hours considered a dereliction of duty that affects the lawfulness of one's salary and the acceptance of charity?

If recreation is customary in your company's work, then there is no blame upon you for it, and you are not considered negligent. This is because what is known by custom is like what is stipulated by condition, and it is considered equivalent to an explicit condition as long as it does not contradict a text.