https://github.com/OpenCPN/OpenCPN/issues/1494#issuecomment-588475680

diff -ur OpenCPN-5.0.0_n/src/glChartCanvas.cpp OpenCPN-5.0.0/src/glChartCanvas.cpp

--- OpenCPN-5.0.0_n/src/glChartCanvas.cpp	2019-03-23 01:25:59.000000000 +0000

+++ OpenCPN-5.0.0/src/glChartCanvas.cpp	2020-02-19 12:20:42.043920729 +0000

@@ -31,7 +31,7 @@

 #endif //precompiled headers

 #include <wx/tokenzr.h>

-

+#include <GL/glx.h>

 #include <stdint.h>

 #if defined( __UNIX__ ) && !defined(__WXOSX__)  // high resolution stopwatch for profiling