[MacPorts] #62220: KeePassXC @2.6.4: no member named 'MacOSBigSur' in 'QOperatingSystemVersion'

[MacPorts]

#62220: KeePassXC @2.6.4: no member named 'MacOSBigSur' in
'QOperatingSystemVersion'
------------------------+-----------------------
  Reporter:  thetrial   |      Owner:  (none)
      Type:  defect     |     Status:  new
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:  2.6.4
Resolution:             |   Keywords:  elcapitan
      Port:  KeePassXC  |
------------------------+-----------------------

Comment (by thetrial):

 Comment to my question under your mentioned
 [https://github.com/qt/qtbase/commit/19d32f0a5fc8b12e03a84ab6e18845337fd3b70f
 Qt commit]:

 ''No upstream-supported version of Qt supports El Capitan (Qt 5.12
 supports macOS 10.12 and up), but back-porting this to non-supported Qt
 versions (in macports, if that's what you're referring to), shouldn't be
 too hard.''

 Does anyone know how to realize that?

-- 
Ticket URL: <https://trac.macports.org/ticket/62220#comment:3>
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