This is my Zigbee Network... i only have zigbee (house is about 15-20m)
But i do get these 'unknown' devices... and even in the build in mapping i can't click anything.
Have you been trying to add a new Zigbee device to your hub recently?
A Tuya Zigbee Curtain Switch as example?
Hi,
I tried 1... a year back and it didn't work. So i tossed it away. Only had one and the rest of my bulbs, motion sensors and outlets all seems to be working etc. And next door is a 90+ woman so not her messing with me 
Go to zigbee details, click the msgs column to sort by msgs (lowest to highest). Are any of them 0?
I would suggest doing a Rebuild Network on the Zigbee Details page. That worked for me to get rid of the Unknowns.
As proposed by @velvetfoot , the 'Rebuild Netwok' button (available on C-8 models only!) will most probably purge these non-existent device IDs from the map.
BTW, the Tuya Zigbee Curtain Switches are (should be) already supported in the community Zemismart Zigbee Blind driver. If you have not tossed it too far away, you can try again .. : )
I don't have that option, i'm running a ancient C5.
Since i only use Zigbee and a few wifi (kasa-plugs) i don't really see the need to 'upgrade'.
I do have a few... but less then the 'unknow'... for example i have in the list a ikea plug but that plug is damaged and not in use anymore, i think it in a bin with some other old electro stuff.
Did you remove it from hubitat itself?
I kinda did. First i left it on there but when i noticed those unknown i removed it. The picture is from a day or 2 after i removed it and some unused virtual devices/buttons.
I hope with threaf/matter a new hub for zigbee users will come out.
But i'm waiting, no big changes for zigbee only (ab)users
This graph is useless in that form... I don't see any helpful information in it. We need to be able to filter and see the last known routes only.
Can you install and run the original community app?
i did some hunting and now i have no device having a 0...
I removed 1 who was not in use anymore and reconnected 2 bulbs.
still I have 3 green unkown dots and 1 blue unknown. Blue one is just going into a loop.
All my devices are connected and running so what now? 
gonna check my electronics trash bin... now i have wifi - smart life controllers... they don't work with Hubitat. I only need it to open/close, no halfway stuff for my roller shutters.
Yes, having so many Zigbee routing devices makes the map difficult to analyze... : (
Is the 'Deadbolt Front' one of the devices that you experience problems with? The map shows it connected via the ''Hallway Light', which device is shown in gray color - this means it doesn't work well as a repeater/router (outCost=0).
What model/make are the devices shown in gray?
Just updated this. Now I'm getting a constant http fetch 404 error. Anyone else getting this problem?
Download the Hubitat app
