Is it permissible to visit chat websites with friends on "Arab Chat" online after the 'Isha' prayer, knowing that it does not delay one from the prayer? And is it permissible to spend time online after the prayer?

There is no legal impediment to chatting if it is about beneficial matters, free from prohibitions such as backbiting, slandering, obscene language, and establishing relationships with foreign women, and does not lead to missing the Fajr prayer in congregation. However, if the chat is about useless matters or includes something forbidden, then it is not permissible. This ruling also applies to the use of the internet.