Trayer can be used as an XEmbed compatible dock for applications which need
this in a Plasma 5 environment.
Trayer is similar to wmsystemtray in that regard, but it looks better.

In Plasma 5 you can start it like this and it will place itself in the
lower right corner, directly above the Plasma 5 system tray, expanding its
size on-demand:

$ trayer --edge bottom --widthtype request --align right --distance 30 &