No special glasses are needed! But it's difficult to trick your mind. Here are some steps to try:
Leave Xmas mode for your first try.
Create a divider to hold or hang over your monitor so each eye sees only its own image and not the other. Use a piece of cardboard or a
manilla folder extended from the screen between the images. Be sure that with either eye closed you only see one image. Getting this right
will make a big difference.
Find a good place in the Mandelbrot set that doesn't drop down too quickly, especially on the left and right sides. The two images will look similar.
Or let us take you to a good place. The "Morph" options tend to produce shallower regions.
For texture settings select only "darken"
Slide "Z Adjust" right and "Dark Adjust" left. This flattens the image. Once you see the flat image as a single image
you can adjust these back (or have a friend do it while you stay focused on the scene).
Check the separation of the images. The flattened images should be separated by less than the distance between your eyes -- ideally about half, or a bit less for your first try.
There is no adjustment currently, but you can magnify or shrink your browser window. (+/- in Chrome.)
Stare at the images from a reading distance, with your head level.
Allow your eyes to correct your double vision. Your mind should naturally
adjust your eyes to bring the two images together as one.
The 3-D structure is beyond the screen. Let your eyes take you there. In fact, reach your finger around your monitor behind the images and try to look through the screen at your finger.
If you can't get it after trying for a few minutes, press the space bar. A dot will shoot step-by-step into the screen. Focus on the dot, following it into
the great beyond.