Earlier quoted context omitted.
Keepass and its various forks are open source. Keepass itself uses dotNet so Linux guys need mono which not all people like. Those people use KeepassXC (a fork of KeepassX which is Keepass in C++ and is unmaintained). I use Keepass. Reasonable security but ugly gui in linux due to mono. Has plugins. Completely offline.
Have you used KeepassXC. I am panning to move to it from lastpass, and want to make sure I am making the right choice.
Other than that it has better gui if that is your thing (Keepass is ugly). It is mostly a fork of keepassx which is still usable but KeepassXC merged all pull requests and fixed a load of bugs in keepassx after the maintainer stopped maintaining. Try it. It works. It also has mutilple releases (snap, appimage etc.).