Dear Hans,

I can’t believe it!
After updating ConTeXt, all the errors are disappeared!

Here is the beginning of the log file before updating:
…
This is LuaTeX, Version 1.0.3 (TeX Live 2017/dev) 
 system commands enabled.
open source     > level 1, order 1, name '/Users/graph/ConTeXt/tex/texmf-context/tex/context/base/mkiv/cont-yes.mkiv'
system          > 
system          > ConTeXt  ver: 2017.01.27 14:39 MKIV beta  fmt: 2017.2.16  int: english/english
system          > 
…

This is the current one:

"cont-yes.mkiv"
This is LuaTeX, Version 1.0.3 (TeX Live 2017/dev) 
 system commands enabled.
open source     > level 1, order 1, name '/Users/graph/ConTeXt/tex/texmf-context/tex/context/base/mkiv/cont-yes.mkiv'
system          > 
system          > ConTeXt  ver: 2017.03.02 22:23 MKIV beta  fmt: 2017.3.11  int: english/english
system          > 


Thank you and have a nice weekend.

Best regards,

Dalyoung