I was also sent this by another priest:

In case you did not know, and would like to take part – or just observe! Good occasion to come together in spirit:

This evening at  18:00 Rome time (so, 17:00 GMT for those of us in the British Isles), the Holy Father will be giving an extraordinary ‘Urbi et Orbi’ address to St Peter’s Square, which will be empty apart from the Crucifix of the Chiesa di San Marcello al Corso, which is associated with a miraculous deliverance of the city of Rome from the plague in 1522, after its 16-day procession around every quarter of the city.

As with every ‘Urbi et Orbi’ speech, an Indulgence is available to all those who receive the Benedictio Papalis (Papal Blessing) at the end, including over TV, wireless, or internet (conc. 4). As most of us cannot receive Holy Communion, only a partial indulgence may be available this time, unless the Church explicitly commutes the usual conditions for a plenary indulgence*, or we could offer the last confession and communion we received for that purpose, assuming we haven’t done so already!