The binary that works is in the home directory.
The one that does not is in usr/local/bin.
The Qt5 libs are in /opt.
The error message from running sigil is this:
error while loading shared libraries: libQt5Widgets.so.5: cannot open shared object file: No such file or directory
I am guessing that somehow the path of the sigil command is wrongly set and so it cannot see the file, which is really there?
But the other thing I can't understand is why the compile and installer should have apparently installed binaries in /home? Or is the installation process first to compile, and then to move the bits into the right places, and this has not happened?
On the other hand, the sigil binaries are where they should be, so the qt5 libs should be also.
What the world needs is a Debian maintainer for sigil! Any volunteers?
Al