Theresa: "I totally agree with yr Emergency Bulletin. It's true "Yr" means neither something that belongs to You, or implying something about You as a person or what You as a person is about to do. Yr means 'yer.'
"Frinstance: 'Yer being a short-sighted prescriptivist, oh Lizzie' can be shortened to, 'Yr being a short-sighted prescriptivist, oh Lizzie.' For further examples of 'Yer' to 'Yr' conversions, see: 'Yer a scallywag!' or 'You forgot yer bag' or 'Yer mother was a hamster and yer father smelt of elderberries!'"