Just because code stops being worked on doesn't mean it immediately "rusts" like metal would. It'll still compile and work the same way it did the last time (unless something changed underneath it).

In addition, there's a few more important things to keep in mind there:

• The number of people working full time on QtWebkit (when it was "alive") was something like 5-6x the number of people working on the Sailfish browser full time.
• QtWebkit has a much longer history than the Sailfish browser: it was released initially alongside Qt 4.4, in 2008. The Sailfish browser UI was initially started on in February 2013[1], later released at the end of the year with the Jolla phone. The Gecko work it uses dates back quite a long time, but has changed UI architecture a number of times, so it is also quite new on the side of platform ports.
• QtWebkit also shipped in a multitude of finished "products" (the N9 being the most prominent talked-about example here, but I've worked on a few others, and heard of a lot more in addition) over those years, compared to Sailfish's grand total of one (so far).

[1]: https://github.com/sailfishos/sailfi...8cd9e22fc47e98