Why does the 'Open Selected Entity' not working in the VHDL or Verilog HDL file?

Description

Due to a problem in the Intel® Quartus® Prime Pro Edition software version 18.1 Update 2 and Intel® Quartus® Prime Standard Edition software version 18.1 Update 1 and earlier, you may see that the 'Open Selected Entity' is grayed out when you right click on the entity name in VHDL or Verilog HDL file. 

Resolution

This problem is fixed beginning with the Intel® Quartus® Prime Pro Edition software version 19.1.