
A device is optimized (or certified) when the plugin has a configuration file for its model, in the z4d-certified-devices database: the widgets to create, the reporting to set up, the device-specific decoding are known and tested.
A device is non-optimized when no work has been done yet to integrate its model. The plugin then relies on the Zigbee standard: during pairing it discovers what the device offers (endpoints and clusters: on/off, level, color, window covering, temperature…) and creates widgets from that.
You can see which devices are optimized:

Two cases:
In both cases, sharing the device data helps get the device optimized, for you and for the other users.
Go to Management > Devices, click the device row to open its details, and click Copy device info (before plugin 9.1.009: click the orange icon of the device in the Optimized column). Its discovery data (what the plugin learned during pairing) is copied to the clipboard. This is the minimum needed to work on the device.

If the details show Please create the device info on the Blakadder line, you can also add the device to zigbee.blakadder.com.
If asked, also download the full device data: Tools > Data, Devices (raw), Download (it saves a z4d-zdevice-raw.json file; before plugin 9.1.009: Tools > Tools, Plugin Raw Devices, then Export, which saves export.json).
You can write the configuration file of the device yourself and put it in the Conf/Local-Devices folder of the plugin, where updates don’t touch it. See:
Conf/Local-Devices precedence.Please share the file in the issue, so that it can be added to the certified database for everyone.