This is unlikely to have anything to do with 1.1.1 but just happens to show up.
These errors cause problems on various browsers and circumstances. If you have HTML errors causing problems, you may not see them on your machine with 1.1, yet other people on other machines and other browsers may, so you want to fix them if they are here 🙂
if you have checked for errors and cannot find any, may be delete the theme and reinstall, and check deactivating ALL plugins to be sure