viewer in hex mode sometimes shows "-" incorrectly

Midnight commander:

Curious bug of "View Hex":
Depending on the name of a file (with or without extension .2)
      and on the directory(!)
the internal viewer with the hex option shows
the 1-byte ASCII character "-"
    as (incorrectly) as 3 bytes "E2 80 90"
    or (correctly) as 1 byte "2D".
This is demonstrated by screen shots taken with a 6-byte file,
but was discovered accidently with a larger file.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: mc 3:4.8.15-2
ProcVersionSignature: Ubuntu 4.4.0-112.135-generic 4.4.98
Uname: Linux 4.4.0-112-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.15
Architecture: amd64
CurrentDesktop: Unity
Date: Sun Feb 18 14:10:37 2018
InstallationDate: Installed on 2016-11-12 (462 days ago)
InstallationMedia: Ubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
SourcePackage: mc
UpgradeStatus: No upgrade log present (probably fresh install)