Bug#979638: gpsprune: fails to start because of missing resources (texts)

[activityworkshop]

Package: gpsprune
Version: 20.1-1~bpo10+1
Severity: important

Dear Maintainer,

After upgrade from 20 to 20.1 using stable-backports, GpsPrune now fails to start from the main menu.
When started directly from the console, it gives the following error:

$/usr/bin/gpsprune 
Exception in thread "main" java.util.MissingResourceException: Can't find bundle for base name tim.prune.lang.prune-texts

It seems that all the translation files under tim/prune/lang are not present in the jar /usr/share/gpsprune/gpsprune.jar
although they are visible here:
 https://sources.debian.org/src/gpsprune/20.1-1/tim/prune/lang/
so I guess this is just a build / packaging problem?

Thanks very much for your support!

-- System Information:
Debian Release: 10.7
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.19.0-13-amd64 (SMP w/6 CPU cores)
Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8), LANGUAGE=en_GB.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages gpsprune depends on:
ii  default-jre [java9-runtime]     2:1.11-71
ii  openjdk-11-jre [java9-runtime]  11.0.9.1+1-1~deb10u2

Versions of packages gpsprune recommends:
ii  gnuplot-x11             5.2.6+dfsg1-1+deb10u1
ii  gpsbabel                1.5.4-2
ii  libimage-exiftool-perl  11.16-1
ii  libjava3d-java          1.5.2+dfsg-16
ii  libjava3d-jni           1.5.2+dfsg-16
ii  libvecmath-java         1.5.2-7

gpsprune suggests no packages.

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