[sliken]

Not sure I'd say "no holes", but yes there are no islands, the entire mandelbrot set is connected. However that does not mean that parts of the display that's interesting doesn't cover part of the set, that's not visible in any individual pixel.

For those that want to fly around in the mandelbrot set, even a 2015 desktop can easily keep up, I suggest Xaos which I believe includes all the common mandelbrot optimizations at https://xaos-project.github.io/

There's even a web version at the above URL. It's in most linux repos I tried apt or yum. I couldn't find any docs for what optimizations Xaos uses, but it seems plenty fast for real time zooming, even on old hardware.