moserial has a defective desktop file. When updating file association it show this error message
Error in file "/usr/share/applications/moserial.desktop": "" is an invalid MIME type ("" does not contain a subtype)
The real problem cause by its desktop files
[Desktop Entry]
Type=Application
Name=moserial Terminal
Comment=A serial terminal optimized for logging and file capture
StartupNotify=true
Exec=moserial %U
Icon=moserial
Categories=GTK;Utility;FileTransfer;TerminalEmulator;Network;System;
MimeType=;
Comment[ca]=Un terminal sèrie optimitzat per a l'enregistrament i la captura de fitxers
Comment[cs]=Sériový terminál optimalizovaný pro ukládání záznamu a zachytávání souborů
Comment[da]=En seriel terminal optimeret til logning og filoptagelse
Comment[de]=Ein serielles Terminal für das Mitschneiden und Aufzeichnen
Comment[es]=Un terminal serie optimizado para registro del sistema y captura de archivos
Comment[fr]=Un terminal série optimisé pour la journalisation et la capture de fichiers
Comment[pt_BR]=Um terminal serial otimizado para gravação e captura de arquivo
Comment[sl]=Terminal prilagojen za beleženje in zajemanje datotek
Comment[sv]=En seriell terminal optimerad för loggning och filfångst
Comment[zh_CN]=为登录和文件获取专门优化的串行终端
GenericName[ca]=Terminal sèrie
GenericName[cs]=Sériový terminál
GenericName[da]=Seriel terminal
GenericName[de]=Serielles Terminal
GenericName[es]=Terminal serial
GenericName[fr]=Terminal de port série
GenericName[nb]=Seriell terminal
GenericName[pt_BR]=Terminal serial
GenericName[sl]=Terminal
GenericName[sv]=Seriell terminal
GenericName[zh_CN]=串口终端
Name[ca]=Terminal moserial
Name[cs]=Terminál moserial
Name[da]=moserial terminal
Name[de]=Serielles Terminal
Name[es]=Terminal moserial
Name[fr]=Terminal moserial
Name[nb]=moserial terminal
Name[pt_BR]=Terminal moserial
Name[sl]=moserial terminal
Name[zh_CN]=moserial 终端
As you see here that MimeType was value was ";". The MimeType field must be removed from the desktop since there is no file association for moserial. Please fix the package