Offline Devices not showing on web interface
Two web apps are completely independent. Using one would never affect the other one in any way.
As for the "old" web app, it hasn't had any major changes recently. My guess you just have a filtering enabled.
All devices are listed in the "Devices" pane and no filters applied there. The "Status" pane is blank for the missing devices. Are there other filters to check?
Wait. How do you see "status" panel if device is missing? Do you mean location is missing, not device?
Also, the devices are all present on map with "State" information in the Modern interface at the same I login to with the old interface and those devices have blank State and missing from map.
I would recommend checking browser console. Usually an issue like this happens when you have invalid coordinates.
What should I look for in the console? I don't understand how everything is OK in the Modern interface (device co-ordinates and all other device state information showing correctly) but missing from the old one?
Solved. One of the devices has ended up with a category = 0. I changed it back to "arrow" and everything works.
Explanation: I use the "arrow" category and changed one device category in the Modern interface to see how it looks. In the Modern interface I then selected the blank entry at the top of the category dropdown to remove the icon, and it sets category to zero - which the old interface doesn't like.
I recently upgraded to 4.11. Now in the "old" web interface my user is missing most offline devices. They will show when the device goes online, and it is only affecting my user. I guess it is because I have been looking at the Modern interface. Is there some setting I have inadvertently changed that this should happen?