Application launchers in '/usr/share/applications' not working in Nautilus
Solution 1:
You are welcome to new brave world of modern GNOME Shell "desktop".
It is a bug 1819375 caused by upstream Nautilus simplification.
You have to use other fully-functional modern file-managers like Caja, Dolphin, Konqueror, Nemo, PCManFM or Thunar.
If you want to get normal fully-integrated non-surprising desktop back - remove GNOME Shell and install other normal desktop. You may want to follow my Q&A to do so. My recommendation is to install MATE DE instead.