Something has changed but I'm not sure what.

Consider two forms "A" & "B" and a global timer object responsible for periodically updating form "B". If when typing in a textbox field in form "A", the global timer fires and updates data on form "B", when focus returns to form "A" the cursor is moved back to the left most position in the textbox field on form "A" (appearing to the left of data already entered into that field) as opposed to the cursor returning to where it was when form "A" momentarily lost focus.

This behavior was not always the case, but something has changed. Anyone have any ideas?