So in the single select drop down, user selected '12345678' at first, then user would like to search for '12345679', and currently if user hit 'Backspace' in the selection box, it will clear the whole selection, what I wish is when I hit the selection box, and hit 'Backspace', it will only delete the last digit, which becomes '1234567', so that instead of retyping the whole search term '12345679', I can then just add the last digit at the end.
A similar issue was posted in brianreavis/selectize.js: (https://github.com/brianreavis/selectize.js/issues/610)
So in the single select drop down, user selected '12345678' at first, then user would like to search for '12345679', and currently if user hit 'Backspace' in the selection box, it will clear the whole selection, what I wish is when I hit the selection box, and hit 'Backspace', it will only delete the last digit, which becomes '1234567', so that instead of retyping the whole search term '12345679', I can then just add the last digit at the end.