Bug 1566642

The last updates have fixed this issue.

It's happening again. I have all the 3rd-party extensions disabled.

gnome-shell-3.28.1-1.fc28.x86_64

I am seeing this too after upgrading f27->f28 with:

gnome-shell-3.28.1-3.fc28.x86_64

My interfaces are:

$ nmcli device
DEVICE      TYPE      STATE        CONNECTION 
enp0s31f6   ethernet  connected    Auto    
virbr0      bridge    connected    virbr0     
cdc-wdm0    gsm       unavailable  --         
wlp4s0      wifi      unavailable  --         
lo          loopback  unmanaged    --         
virbr0-nic  tun       unmanaged    --

And I see errors like these in journal:

máj 03 19:38:58 kujon gnome-shell[1331]: JS ERROR: TypeError: item is undefined
                                          _sync@resource:///org/gnome/shell/ui/status/network.js:427:17
                                          wrapper@resource:///org/gnome/gjs/modules/_legacy.js:82:22
                                          _parent@resource:///org/gnome/gjs/modules/_legacy.js:39:12
                                          _sync@resource:///org/gnome/shell/ui/status/network.js:505:9
                                          wrapper@resource:///org/gnome/gjs/modules/_legacy.js:82:22
                                          _addConnection@resource:///org/gnome/shell/ui/status/network.js:306:9
                                          wrapper@resource:///org/gnome/gjs/modules/_legacy.js:82:22
                                          checkConnection@resource:///org/gnome/shell/ui/status/network.js:277:13
                                          wrapper@resource:///org/gnome/gjs/modules/_legacy.js:82:22
                                          _deviceAdded/<@resource:///org/gnome/shell/ui/status/network.js:1761:21
                                          _deviceAdded@resource:///org/gnome/shell/ui/status/network.js:1760:17
                                          wrapper@resource:///org/gnome/gjs/modules/_legacy.js:82:22
                                          _readDevices@resource:///org/gnome/shell/ui/status/network.js:1703:13
                                          wrapper@resource:///org/gnome/gjs/modules/_legacy.js:82:22
                                          _clientGot@resource:///org/gnome/shell/ui/status/network.js:1663:9
                                          wrapper@resource:///org/gnome/gjs/modules/_legacy.js:82:22

The VPN lock icon is also missing when connecting to a VPN.

I'm having the exact same issue that Tomas Vanderka has. The Network and VPN icons are gone.

tested with gnome-shell "3.28.2" and "3.29.1" on ArchLinux.

Same here on Fedora 28 gnome-shell 3.28.2 on two Notebooks and one PC.
All three with Intel-NICs.

Had the same issue on Fedora 28 (upgraded from 27), gnome-shell 3.28.2.1.  This was occurring with the _second_ user.  I found an old thread indicating that there was an issue with connections being made available to other users.  Note that connections on the user account with the issue were coming from the _first_ user.  Unchecked the "Make available to other users" on all connections (or deleted them if now unneeded) on the first user.  All connections now show up properly for the first and second user. (Note some of them had to be created).

This does not resolve the Problem. I previously deleted all connections and created them again (with "Make available to other users" unchecked).
The icon does appear 1 out of 15 reboots. The next time the machine reboots the icon disappears an there are only a view connections visible. 
When I jump between some visible connections the icon appears but it only shows up "connected" where "Wired Connected" should be and you can't see which connection is active.

Having the same issue, wifi connections don't appear in the Gnome Shell menu. When connected only to wifi, I get a "wired connection" icon in the top bar, but no wireless menu and no signal strength indicator. It seems to be tracked upstream with the referenced issue, but nothing has actually happened from the actual developers it seems. Gnome shell is having an increasing number of issues and floods a lot of errors in the log on F28 :-/

My standard connections are not shared among users. So this does not seem to be the problem (or not the only one).

Error message here is slightly different:
JS ERROR: TypeError: item is undefined
_activeConnectionChanged@resource:///org/gnome/shell/ui/status/network.js:371:13
wrapper@resource:///org/gnome/gjs/modules/_legacy.js:82:22

Possibly relevant upstream bug: https://gitlab.gnome.org/GNOME/gnome-shell/issues/140

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