I noticed this problem while trying to answer someone's question post about specialized text input behavior. I also uncovered something else that may or may not be related. In responding to the user's question, I was using an event observer (in JS) to monitor the text input's value changes (input event). I did this before to do real-time evaluation of typed input. In a previous SL version, it all worked as expected (i.e., event handler dispatched after input value changes). In the current SL version, the event handler for the input event is actually dispatched BEFORE the value of the text input is updated, which is very odd. The input value doesn't update until at some point AFTER the event handler is called. I don't know if this relates to the text input cursor positioning issue, but it might if the delayed value update is affecting the selection attribute.