I am using Ubuntu 18.04 with the standard Gnome desktop environment. When switching between applications or windows via keyboard shortcut (as expected) a single press of the shortcut in question will bring you back to the most recently viewed window/app, while multiple rapid presses will cycle you through the full list of entries.
When switching between workspaces, however, the only shortcuts available are "move to workspace above" and "move to workspace below." The utility of these two shortcuts can be somewhat expanded with Gnome-Extensions that cycle the workspace list at the top and bottom, allowing you to rapidly press one or the other for continuous switching. But moving back and forth between two specific workspaces quickly is still rather a pain... Is there anyway to implement the "alt-tab" style one tap = most recent workspace, successive taps = cycle through full workspace list?