> What you cannot do is calling for violence against them.
This is blatantly disingenuous. The Public Order Act 1986, Racial and Religious Hatred Act 2006 and the Criminal Justice and Immigration Act 2008 all criminalize "insulting" and "abusive" words, or any public display of literature that is "insulting" or "abusive" -- much more than calls for violence:
> A person who uses threatening, abusive or insulting words or behaviour, or displays any written material which is threatening, abusive or insulting, is guilty of an offence if—
> (b) having regard to all the circumstances racial hatred is likely to be stirred up thereby.
https://www.legislation.gov.uk/ukpga/1986/64/part/III/crossh...
British jurisprudence has consistently put the likelihood of racial hatred being stirred up to the whims of the presiding judge. If the unaccountable bureaucrat feels like your comments could likely stir up racial hatred to even a single one of your cousins, even if there was no evidence of any stirred, then you are guilty.
What exactly constitutes "abusive" or "insulting" is not only vague but applied solely to white Christians. Certainly a document that says polytheists should be murdered (Quran 9:5) or one that says Hebrews should "completely consume" all the people that they get control of "with no pity" (Deuteronomy 7:16) could be considered not only insulting and abusive, but outright threatening. But these statutes are only used to attack people saying "I don't like how many foreigners are in my country and they should be rounded up and shipped back." Whatever your position on this kind of jingoistic nationalist sentiment, you should be able to recognize that the hypocrisy and lack of liberty is stupid and dangerous and is going to eventually result in genocide (either of the native Britons by the new arrivals, or the latter in the backlash).
Elizabeth Kinney certainly did not "call for violence" against the man who beat her. She simply, minutes after being physically beaten, used a slur in a private text message to a friend, and was arrested for it:
https://www.facebook.com/piersmorganuncensored/videos/elizab...
It is extremely suspect that every thread that Hacker News and other prominent and influential platforms has on these statutes gets flooded by people spreading deliberate pro-government misinformation, claiming that people are only being arrested for "calls for violence".
Threatening violence against parties is generally punished by a separate, far more severe statute (Serious Crime Act 2007, which replaced the traditional mechanism for incitement so that it could be vaguely applied to overeager online comments) that is virtually never invoked for Facebook posts, because none of elderly people arrested under this statute are threatening violence. They are posting something considered unacceptable by the powers that be, because limitless immigration was rammed down the throat of the English without any regard to democratic will or desires.