LXDE Desktop Session Settings

LXDE - Preferences - Desktop Session Settings (lxsession-edit)
entries are read from 2 locations:

 /etc/xdg/autostart
and
 ~/.config/autostart

Ticking a box appends LXDE to the line: "OnlyShowIn="
Unticking does the opposite.
Some ".desktop" files may not appear if they include the entry "hidden=True".

To add a new startup entry you can copy the desktop file from /usr/share/applications.

Notes:
*If dbus is installed daemon's may be being launched from
 /usr/share/dbus-1/services

*For xfce4-notifyd, it may be preferable to simply disable notifications within the app:
 iceweasel -> about:config -> browser.download.manager.showAlertOnComplete
 Dropbox -> Preferences -> Display desktop notifications