In Sierra TotalSpaces2 disables the Mac's "Show Desktop" gesture ("Spread with thumb and three fingers") when the TotalSpaces2 preference "Swipe to change space" is set to 4 fingers. Perhaps because they both use 4 fingers?
This did not happen under El Capitan. Why under Sierra? Or did it start with the last update?
I think it was a consequence of the changes made to handle swiping required for Sierra.
I'm sorry I'm not sure this is going to be easy to fix, but I'll check it.
(I use a hotcorner for Show Desktop but I do understand it's not to everyone's taste.)
Thanks, Stephen. I also set a hotcorner for this.
I really need the "show desktop" gesture functionality to come back. Hot corners on a 27" screen are bit awkward to say the least...