I think it is just a special face powder that photographs better than regular face powder and can’t be seen under ordiary light.
Not a big deal. Shows you the Brits have their heads up their butts if they think this is the most important thing they have to worry about.
Beheadings, trafficking of British schoolgirls and gang rapes are fine but, God forbid someone’s makeup photographs badly.
Shame on them for pointing it out.
Yes, this is caused by face powders containing silica or SPF which reflect the light very strongly. This effect is not visible in daylight but is highly apparent under flash photography. Lots of celebrities have experienced this problem, along with unfortunate brides.