I’ve really had it with the whole feature request nonsense bounded by a limited plex development team.
DLNA is something that others get right, yet somehow years have passed and Plex cannot enable search which makes them obsolete in modern smart home systems. DLNA itself is based on a search of content afforded to Plex and multiple others have implemented it.
So I’m giving this to EOY '18 then saying goodbye to Plex.
To wit: Control4’s list of DLNA supported vendors:
Supported DLNA Servers
The following DLNA music servers have been tested and are fully supported by the driver:
Twonky
Asset
MiniDLNA/Ready Media
WD Live
Buffalo DLNA (Driver version 1.0.1 or higher)
The following DLNA servers are supported but do not provide search capability (note the search icon will still be shown on the UI):
Plex
Synology Media Server (using Simple Style menu)