I currently have Dropbox 3.10.7-1 installed. I am aware of the Plasma 5 incompatibility. I would not like to fiddle with anything if the Dropbox icon will be displayed soon on the system tray as Plasma 5/Dropbox co-evolve. Can someone who knows what is happening please clarify.
Note: xembed-sni-proxy is now in the Manjaro repositories:
sudo pacman -S xembed-sni-proxy
The version of dropbox that is sni compatible, has it statically linked to ubuntu’s version. This means that unless your using the same version of Plasma 5 that dropbox was compiled against, it will not load/work.