LANG=C gwakeonlan
--> all OK
press the + button and see first line of window in bold letters.

LANG=de_DE.UTF-8 gwakeonlan
-->
/usr/bin/gwakeonlan:435: GtkWarning: Failed to set text from markup due
to error parsing markup: Fehler in Zeile 1, Zeichen 73: Element
»markup« wurde geschlossen, aber das derzeit offene Element ist »b«
builder.add_from_file(__searchPath('ui', '%s.glade' % APP_NAME))

press the + button and see first line of window
shown as "<big><b>Rechnername und die MACAdresse eingeben<big><b>"

there are probably the / missing in the closing tags.

cu
erik

Dear submitter,

as the package gwakeonlan has just been removed from the Debian archive
unstable we hereby close the associated bug reports.  We are sorry
that we couldn't deal with your issue properly.

For details on the removal, please see https://bugs.debian.org/945559

The version of this package that was in Debian prior to this removal
can still be found using http://snapshot.debian.org/.

Please note that the changes have been done on the master archive and
will not propagate to any mirrors until the next dinstall run at the
earliest.

This message was generated automatically; if you believe that there is
a problem with it please contact the archive administrators by mailing
ftpmaster@ftp-master.debian.org.

Debian distribution maintenance software
pp.
Scott Kitterman (the ftpmaster behind the curtain)

gwakeonlan was reintroduced to Debian unstable.

Please check if the new version fixes the issue you reported.

If the bug is fixed already, please let us know or close the
bug report in the version where the bug was fixed.

If the bug is not yet fixed, please file an issue upstream on GitHub
and mark this bug report as forwarded to the upstream issue.

https://github.com/muflone/gwakeonlan