Pope Francis was the toast of social media on Wednesday after successfully completing his latest groundbreaking mission: popping out of the Vatican to buy himself some new footwear.

To the barely containable delight of his many fans in cyberspace, the 80-year-old pontiff visited a pharmacy near the Holy See on Tuesday to pick up a pair of the orthopaedic shoes he wears to offset the pain caused by chronic sciatica.

The visit was filmed and snapped on smartphones by a handful of customers who were in the shop at the time and later uploaded images to social media.

A selection of pictures was posted on a Facebook page described as belonging to Rome barmaid Martina Duarte with the caption: "A Tuesday with the Pope... my love I am incredibly proud of you!"

Most of the online comments were similarly breathless in tone, admirers appearing to share Duarte's amazement at the sight of the world's 1.2 billion Catholics doing his own shopping, posing for pictures and blessing a crucifix belonging to one of the shop's staff.

One commenter on Italian daily La Repubblica's site called for Francis to be immediately installed as the new mayor of Rome, while another simply noted, presumably with a disbelieving shake of the head: "The greatness of this man!"

It was not the first time the former Jorge Bergoglio has created a sensation by leaving his modest lodgings in the St Martha boarding house to get essential supplies.

There was similar excitement in September 2015 when he was spotted at his optician near the Spanish Steps in Rome's historic centre.

That in turn recalled the general stupefaction around the time of his election in 2013 when it emerged that he not only carried his own briefcase but also paid his own hotel bills.

Many suspect an element of image construction in these well-publicised moments. But Francis's frugality and fondness for mingling with ordinary people predates him becoming pope.

As bishop of Buenos Aires, local buses were his favoured mode of transport and after becoming pontiff he admitted that the thing he most missed was enjoying the anonymity that would allow him to go into Rome and have a pizza.

Cynics will be reassured that not everyone was bowled over by Francis's latest outing. "The usual, narcissistic exhibitionism," commented a sceptic on www.larepubblica.it.