Meghan, Duchess of Sussex speaks to guests at the Queen's Young Leaders Awards Ceremony, hosted by Britain's Queen Elizabeth II and the Duke and Duchess of Sussex, at Buckingham Palace in London, Tuesday, June 26, 2018. (Yui Mok/Pool Photo via AP)

Sitting with her husband and his grandmother, the new Duchess of Sussex looks elegant, stylish and happy – but are her crossed legs breaching royal etiquette?

That was certainly the opinion of some armchair experts who were quick to take to the internet to pass on their views.

They, however, soon found themselves on the receiving end of some comments from other royal experts – real ones, this time – who pointed out that they had got their facts wrong.

The kerfuffle began when Meghan, wearing a Prada dress, was pictured at a Buckingham Palace reception for the Queen’s Young Leaders this week, sitting with her legs crossed at the knee and stretched to one side – rather than the usual royal ladies’ pose of crossing their legs at the ankle.

The 36-year-old’s relaxed posture sparked an outpouring of criticism on social media.

One critic wrote on Facebook: ‘The Duchess of Sussex has her legs crossed wrong. What a disrespect to the Queen. All royal ladies cross at the ankles or put both legs to the side.’

Another said: ‘It was an act of disrespect to the Queen. She does not learn the rules of royalty.’

However, according to actual royal etiquette experts, while they should not cross their legs at the knee for the practical reason of protecting their modesty from photographers, Meghan did not break any rules.

Myka Meier, founder and director of Beaumont Etiquette, said: ‘There is no official protocol that says exactly how one must sit when near the Queen.’

Instead, it was suggested that Meghan adopts a pose she has used before called ‘the duchess slant’, which was named after the Duchess of Cambridge – keeping both knees and ankles tightly together while slanting the legs to the side.

Britain's Queen Elizabeth II and Meghan, the Duchess of Sussex, using the "appropriate Duchess slant" (Danny Lawson/PA via AP)

Etiquette expert Liz Brewer said: ‘Normally you cross legs at the ankles to avoid any embarrassment. However, there is nothing in writing saying, “Thou shalt not cross at the knees.”?’

Royal biographer Ingrid Seward added: ‘I think it would have been more elegant for her to have adopted the duchess slant.

‘Anyway, she’s committed much worse faux pas than how she’s positioned her legs. I overheard her say, “Pleased to meet you”, which is considered incredibly impolite. A royal must say, “How do you do?”?’