I built lxsession-edit from git and noticed that it didn't generate lxsession-edit.desktop properly. It was supposed to fetch the translations and build the file but it simply copied xsession-edit.desktop.in, thus creating a non-working desktop file (because of the underscores in front of 'Name' and 'Comment').

Also it gave a warning when I ran autogen.sh (IDK if it's important):
Makefile.am:29: `%'-style pattern rules are a GNU make extension