I almost always use fast reply, so I have no idea when this started. Realised it was happening for me today when I tried to quote. Both Add Reply and New Topic do this: I can type in the text field, but cannot select where I want to start typing (below a quote for instance). It forces me to type at the beginning of all text. Pressing Enter/Return works fine however, but arrow keys, or using the cursor pointer do not work, removing the ability to 'move around' in a block of text.