How to use the stereoscopic 3D Side-By-Side view? When working with Render Layers/Views turned on for stereoscopic 3D mode, I can preview the 3D in the OpenGL viewport's camera view numpad 0 in anaglyph (red/cyan glasses etc). That works fine.

But I'd like to also be able to use the Side-By-Side (cross-eyed) mode for previewing in the OpenGL viewport.

When I go to Window/Set Stereo 3D I can change to side-by-side cross-eyed, and I get a message saying Stereo 3D mode requires that the window be fullscreen.

But no matter how I switch to fullscreen I never see a Side-By-Side image. I've tried ctrlup arrow, shiftspace, and altF10, all inside and outside of the camera view, but I never see any side-by-side view.

Is it possible to see a cross-eyed side-by-side view in the OpenGL viewport?

If it's not possible in the OpenGL viewport, is it at least possible to see a rendered image in cross-eyed side-by-side in the UV/Image Editor? Not even that works.

I AM able to save a PNG in side-by-side cross-eyed format. The option from the save menu work fine and will produce a side-by-side cross eyed PNG file. But I don't know how to use the option in either OpenGL preview or in render preview in the UV/Image editor.

I am using Blender 2.78a on Xubuntu Linux. Thanks to anyone for any help.

Related questions:

3D render - requested side-by-side but got anaglyphic - how to fix
This question just talks about how to use the Save Image options to get a side-by-side PNG file. That is not my problem; saving a PNG works fine.

How do I use Blender&#39;s built-in stereoscopic features? Again, just talking about saving a PNG.
To launch fullscreen mode press AltF11.

In the Info Area, go to Window > Toggle Fullscreen.

A search in the Blender Documentation also display the menu location and keyboard shortcut.