If there's bugs you care about, then you patch them. WebKit is open source, so anyone can fork it and build their own version with any fixes or changes they like. I don't see anything but positive news from this.
> WebKit is open source, so anyone can fork it and build
> their own version with any fixes or changes they like.
You're committing an error here. Say you find a bug in Webkit. You patch it, but Apple declines to accept it upstream. You fork the project. Now how do you get your fork into the hands of your users? Unless you're secretly Google in disguise, you're SOL.So now you have a fixed WebKit that nobody else uses.
It's about the same as when you start at a company with a large existing codebase. You're not going to get much done until you've read and understand the chunks of the code that relate to what you need to do. This spinup time is definitely bigger than the hour it can take to fix a bug in a small project that you previously had no experience with, but it's definitely within the realm of the possible.