Problems with Spyder 3 in macOS Sierra

I have recently installed the latest conda distribution on macSierra. I have encountered many problems:

1) My main concern is that Spyder crashes eventually, especially when switching between applications and coming back to Spyder the rotating wheels keeps eternally spinning and unresponsive. This happens after ~10 minutes of use. I have tried spyder with different graphic backend for ipython and the problem still happens. When launching spyder the following message appears:

[warn] kq_init: detected broken kqueue; not using.: Undefined error: 0

repeated 9 times.

3) When plotting figures, figures I create after calling

close('all')

open and close immediately. I never encountered this behaviour previously.

My conda distribution is the following:

           platform : osx-64
      conda version : 4.2.9
   conda is private : False
  conda-env version : 4.2.9
conda-build version : 2.0.2
     python version : 3.5.2.final.0
   requests version : 2.11.1
   root environment : //anaconda  (writable)
default environment : //anaconda
   envs directories : //anaconda/envs
      package cache : //anaconda/pkgs
       channel URLs : https://repo.continuum.io/pkgs/free/osx-64/
                      https://repo.continuum.io/pkgs/free/noarch/
                      https://repo.continuum.io/pkgs/pro/osx-64/
                      https://repo.continuum.io/pkgs/pro/noarch/
        config file : None
       offline mode : False

The problem is not with Spyder itself but with Qt, the graphical library on top of which Spyder is built on.

The current Qt version in Anaconda (5.6.0) does not support macOS Sierra. According to this Github comment, the first versions that do it are 5.6.2 and 5.7.1.

As soon as Continuum (the company behind Anaconda) updates Qt to one of these versions, I'm pretty sure those strange problems you're seeing will be solved.