Is it sufficient to recite the supplication for the expiation of a gathering (kaffarat al-majlis) after leaving the place where there was much idle talk, as long as the person is still within the general vicinity of that place? And is it permissible to offer the expiation of a gathering by reciting it before shutting down a computer, with the intention of expiating the idle talk that occurred while using it?

The expiation for a gathering (Kaffarat al-Majlis) is to say: "Glorified are You, O Allah, and with Your praise, I bear witness that there is no god but You, I seek Your forgiveness and I repent to You." This is recited at the end of the gathering, or upon standing up from it, or intending to do so. If someone leaves the gathering and departs from it, the time for this supplication has passed for them, and reciting it thereafter becomes a general supplication or remembrance. However, if the conversation via the device included idle talk, then the person who spoke can offer the expiation for the gathering as long as they are still in their own gathering, even if they have closed the device.