First I downloaded and installed https://dev-builds.libreoffice.org/daily/master/Linux-rpm_deb-x86_64@86-TDF/current/master~2019-05-04_04.44.35_LibreOfficeDev_6.3.0.0.alpha0_Linux_x86-64_deb.tar.gz. That worked. Then I tried to download and install the German help system for it. But that did not work because the installed Version of LO speaks English. - That's ok for me. Then I downloaded https://dev-builds.libreoffice.org/daily/master/Linux-rpm_deb-x86_64@86-TDF/current/master~2019-05-04_04.44.35_LibreOfficeDev_6.3.0.0.alpha0_Linux_x86-64_deb_helppack_en-US.tar.gz and unpacked the file to ~/Downloads/tmp/LibreOfficeDev_6.3.0.0.alpha0_Linux_x86-64_deb_helppack_en-US/. I found a dictionary DEBS in it and therefore I issued $ cd ~/Downloads/tmp/LibreOfficeDev_6.3.0.0.alpha0_Linux_x86-64_deb_helppack_en-US/DEBS/ $ There I issued the command $ sudo dpkg -i *.deb Vormals nicht ausgewähltes Paket lodevbasis6.3-en-us-help wird gewählt. (Lese Datenbank ... 303232 Dateien und Verzeichnisse sind derzeit installiert.) $ However, after trying to open help, firefox opened and wanted to show me file:///tmp/lu11967av05m5.tmp/NewHelp1.html However, there is no such file. Nor is there any NewHelp1.html on the whole computer. What is necessary to install the en-US help for this development version of LO?
Adalbert, your question is not a bug. Please use Ask LibreOffice (https://ask.libreoffice.org/de/questions/) or the german mailing list users@de.libreoffice.org. I suppose you will get an answer sooner than in Bugzilla.
I followed your advice and posted https://ask.libreoffice.org/de/question/192756/vergeblicher-versuch-hilfe-zur-entwicklerversion-zu-installieren/