Solved
CubeIDE unmet dependencies on Ubuntu are old versions.
Cannot install on Ubuntu 23.10. This release of Ubuntu comes with libncurses6 and libpython3, which are installed on my system. Using the .DEB release downloaded from https://www.st.com/en/development-tools/stm32cubeide.html.
EDIT: Tried with both Wayland and XORG. The install fails in the same way for both.
The following packages have unmet dependencies:
st-stm32cubeide-1.14.0 : Depends: libncurses5 but it is not installable
Depends: libpython2.7 but it is not installable
E: Unable to correct problems, you have held broken packages.
