I think there's something wrong with the woman.
Earlier this week I was thinking about the "final solution" tweet, and wondering if there was any possibility she didn't know what it meant. And after some reflection, I concluded, no, there wasn't. Everyone of that age has heard the term "final solution". So she must have done it deliberately.
And assuming she doesn't actually want to herd all Muslims into gas chambers and kill them, I can only guess that she must have done it for purely attention-seeking reasons. That here was an event - the Manchester bomb - that wasn't about her, and here was a chance to make it about her. Because she cannot bear to go more than five minutes without being the centre of attention. That suggests someone who isn't, to put it kindly, quite right in the head.