I changed the color profile in OS X and that sorted it for me.
See the screenshots below using a different color profile. Please note that in the screenshots I try #ff00ff , #ff1aff , #ff33ff and #ff4dff . Only when I do not select the standard OS X color profile will I be able to distinguish colors correctly.
Default color profile:

With a different color profile:

From: CSS colors in OS X render correctly in Firefox, but incorrect in Safari and Chrome (potentially "resolved")
I found that Safari and Chrome cannot #ff00ff , #ff1aff , #ff33ff and #ff4dff . But Firefox could. Also, Inkscape, an X11 application, can. But Gimp and Libreoffice Writer, which are not X11 applications, failed. Firefox and X11 apps seem to somehow use their own color profile.
I have no idea why the Mac by default uses the Color LCD profile, which does not make this distinction among others.
newfivefour Mar 31 '19 at 0:43 2019-03-31 00:43
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