message: Suspend wxLog while background task is running
  Suspend wxLog flushing temporarily while a (window-)modal progress
  window is shown. This has the effect of ensuring that the log is shown
  to the user only after the progress window is dismissed, preventing
  possible UI state race conditions.
diff: @@ -105,6 +105,10 @@ protected:
  m_progress = std::make_shared<Progress>(1);
  attach(*m_progress);
  + // don't show any flushed log output until the modal progress window closes:
  + // FIXME: proper UI for showing logged errors directly within
  + wxLog::Suspend();
  +
  auto bg = dispatch::async([=]
  {
  Progress progress(1, *m_progress, 1);
  @@ -116,6 +120,7 @@ protected:
  // Show*Modal() was called (which could happen if `bg` finished instantly):
  CallAfter([=]{
  EndModal(wxID_OK);
  + wxLog::Resume();
  });
  });
  // TODO: handle exceptions (can't just rethrow on main thread)
  