Last month, British authorities suggested that perpetrators could be hit with fines in Germany if they refused, when asked, to stop singing such songs, and if deemed sufficiently provocative, to qualify as a possible public order offence.

However, German police have also said there is a limit to what they can do because singing the song is not a criminal offence in the country, unlike Nazi-related gestures or the chanting of discriminatory racist or homophobic songs.

The practicalities of stepping in when hundreds of fans may be singing such a song also has to be taken into account.

“It depends on the circumstances. First they can expect communication, [and asked] ‘what are you doing?’” said Oliver Strudthoff, the head of Germany’s National Police Co-ordination Centre, when I asked him last month how such behaviour would be handled during the Euros.

“It’s perhaps not an offence, but it’s very, very impolite. So please stop this,” he said, suggesting a fine or even arrest could follow if the behaviour became more serious.

A spokesperson from the UK Football Policing Unit said: “The vast majority of supporters travelling will be genuine fans who simply want to enjoy the football. We would urge any fans travelling to be mindful and aware of the local culture and be good guests.

“Wilfully acting in a way to cause offence could result in a heightened risk to your personal safety, and German police will take action against those breaking the law. This action can include heavy fines and custodial sentences.”

“I just think it’s pretty dull and boring” chief constable Mark Roberts, the national lead for football policing, told BBC Sport.

“The Germans are fairly even handed about it. There is a limit, though. As with public order legislation in this country, we see a lot of controversy about things that people say. Is it an offence? Is it not? We can’t give black and white rules on it. It is context specific.

“We saw in Munich the last time England played there. The Germans were tolerant to a point. But when people overstepped the mark, they were arrested and dealt with.”