It seems a bit odd to me to credit Total Commander but not a single one of Midnight Commander, Windows Commander, EF Commander, WinNC, PC Commander, SpeedCommander, XCommander, XTree, YTree, ZTree, or the venerable Norton Commander.
It even still uses the same hotkeys as Norton Commander. Still, it supports Total Commander's plugins in case someone is using those, it's LGPL, it looks like a decent example of a useable Free Pascal application to dive into contributing against, it's cross-platform (Windows, Linux, FreeBSD, macOS), and it builds against gtk2, qt4, or qt5. Overall it looks like a nice project. It could probably use a commit in the About page for a first contribution to the project noting a little more history of its lineage.
It even still uses the same hotkeys as Norton Commander. Still, it supports Total Commander's plugins in case someone is using those, it's LGPL, it looks like a decent example of a useable Free Pascal application to dive into contributing against, it's cross-platform (Windows, Linux, FreeBSD, macOS), and it builds against gtk2, qt4, or qt5. Overall it looks like a nice project. It could probably use a commit in the About page for a first contribution to the project noting a little more history of its lineage.