The folks who develop the alternative web browser Opera are working on improving page loading time, and if their own benchmarks are any indication, those efforts have paid off.
Opera 43 shows significant speed gains over Opera 42, due mainly to the introduction of two new technologies: ‘instant page loading’, which predicts the site you’re looking for as you’re typing in the address bar, and PGO, which optimizes the browser code to make it run faster when it’s most important.
The new version also includes improvements to URL highlighting/selecting. Previously, there was no way to highlight linked text. With Opera 43, highlighting linked text works as expected if you use a horizontal motion, and if you use a vertical motion, the entire link is copied, as before.
There are loads of other changes in Opera 43, as you can see from the lengthy change log. However, none of the changes seem to be related to security vulnerabilities.