[perl #131366] [BUG] Mixining in Blob role gives "P6opaque: missing attribute protocol in compose"

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# New Ticket Created by  Zoffix Znet 
# Please include the string:  [perl #131366]
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# <URL: https://rt.perl.org/Ticket/Display.html?id=131366 >


IRC: https://irclog.perlgeek.de/perl6-dev/2017-05-25#i_14636647

16:02   Zoffix  m: class Foo does Blob {}
16:02   camelia         rakudo-moar 428324: OUTPUT: «5===SORRY!5=== Error while 
compiling <tmp>␤P6opaque: missing attribute protocol in compose of Foo␤at 
<tmp>:1␤»