OS: Debian 10 LXDE 64bit
Lazarus 2.0.12
FPC 3.2.2
TMS FNC UI Pack v3.6.0.0
To install the package I had to change the letter b to B and that
LCLTMSFNCEditorToolbar.pas -> LCLTMSFNCEditorToolBar.pas
and
LCLTMSFNCUIPackPkg
uses LCLTMSFNCEditorToolbar, -> LCLTMSFNCEditorToolBar,