icecat is missing a desktop file and thus it doesn't show up in any application menus. Comparison with hexchat (which does have it) below:
$ find /gnu/store/vwbw8070vy7ikaxbgs6pmi0isw3yzxvm-icecat-38.6.0-gnu1 -name "*.desktop" $ find /gnu/store/vz1cs171wyj9bq48r4kz8s56hpk6gayy-hexchat-2.10.1 -name "hexchat.desktop" /gnu/store/vz1cs171wyj9bq48r4kz8s56hpk6gayy-hexchat-2.10.1/share/applications/hexchat.desktop $ cat /gnu/store/vz1cs171wyj9bq48r4kz8s56hpk6gayy-hexchat-2.10.1/share/applications/hexchat.desktop [Desktop Entry] Name=HexChat Name[de]=HexChat Name[en_GB]=HexChat Name[es]=HexChat Name[fr]=HexChat Name[it]=HexChat Name[ja_JP]=HexChat Name[ko]=헥스채트 Name[pl]=HexChat Name[sq]=HexChat Name[zh_CN]=HexChat GenericName=IRC Client GenericName[de]=IRC-Client GenericName[en_GB]=IRC Client GenericName[es]=Cliente de IRC GenericName[fi]=IRC Client GenericName[fr]=Client IRC GenericName[it]=Client IRC GenericName[ja_JP]=IRCクライアント GenericName[ko]=IRC 클라이언트 GenericName[pl]=Klient IRC GenericName[sq]=Klient IRC GenericName[zh_CN]=IRC 客户端 Comment=Chat with other people online Comment[de]=Chatte online mit anderen Leuten Comment[en_GB]=Chat with other people online Comment[es]=Chatea con otras personas en línea Comment[fr]=Parlez avec d'autres personnes en ligne Comment[it]=Chiacchiera con altri utenti online Comment[ja_JP]=他の人とオンラインチャットをします Comment[ko]=온라인에 있는 사람들과 대화합니다 Comment[pl]=Rozmawiaj z innymi ludźmi przez internet Comment[sq]=Bisedoni në linjë me persona të tjerë Comment[zh_CN]=与其他人在线聊天 Keywords=IM;Chat; Keywords[de]=IM;Chat; Keywords[en_GB]=IM;Chat; Keywords[es]=IM;Chat; Keywords[fr]=IM;Chat; Keywords[it]=IM;Chat;Messaggistica Istantanea;IRC; Keywords[ko]=IM;인스턴트 메신저;Chat;대화; Keywords[pl]=IM;Chat; Keywords[sq]=IM;Fjalosje; Keywords[zh_CN]=IM;聊天; Exec=hexchat %U Icon=hexchat Terminal=false Type=Application Categories=GTK;Network;IRCClient; StartupNotify=true X-GNOME-UsesNotifications=true MimeType=x-scheme-handler/irc;x-scheme-handler/ircs; Actions=SafeMode; [Desktop Action SafeMode] Name=Open Safe Mode Name[de]=Im sicheren Modus öffnen Name[en_GB]=Open Safe Mode Name[es]=Abrir en modo seguro Name[fr]=Ouvrir le mode sans échec Name[it]=Apri modalità sicura Name[ja_JP]=セーフモードで開く Name[ko]=공개 안전 모드 Name[pl]=Otwórz tryb bezpieczny Name[sq]=Hap Mënyrën e Sigurt Name[zh_CN]=打开安全模式 Exec=hexchat --no-auto --no-plugins
