Missing "x" on tab for open files in editor

Description

Missing “x” symbol on tabs for open files in editor. The “x” used to be an icon to close the file.

What steps will reproduce the problem?

1. Open any file in the editor. The tab for that file does not have “x” symbol to close the file. But if you click on the tab in the area where the “x” used to be you still manage to close the file.

What is the expected output? What do you see instead?

Please provide any additional information below

Version and main components

• Spyder Version: 3.1.4
• Python Version: 2.7.13
• Qt Versions: 5.8.0, PyQt5 5.8.2 on Darwin

Dependencies

pyflakes >=0.5.0 :  1.5.0 (OK)
pep8 >=0.6       :  1.7.0 (OK)
pygments >=2.0   :  2.2.0 (OK)
qtconsole >=4.2.0:  4.3.0 (OK)
nbconvert >=4.0  :  5.2.1 (OK)
pandas >=0.13.1  :  0.19.2 (OK)
numpy >=1.7      :  1.12.1 (OK)
sphinx >=0.6.6   :  1.6.2 (OK)
rope >=0.9.4     :  0.10.5 (OK)
jedi >=0.9.0     :  0.10.2 (OK)
psutil >=0.3     :  5.2.2 (OK)
matplotlib >=1.0 :  2.0.0 (OK)
sympy >=0.7.3    :  None (NOK)
pylint >=0.25    :  1.7.1 (OK)

[denson]

I found a workaround:

Change the Qt windows style to either Fusion or WIndows in Preferences > General > Appearance > Qt windows style

It is ugly (by Mac standards) but works.

[d-rams]

After trying this workaround, I now have ‘x’ boxes but they do nothing.

pyqt 5.9.2, spyder 3.3.1, mac osx 10.14