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I have seen relevant solutions in askubuntu and other sites but none worked for me so far.
I reinstalled network manager, modem manager, tried to upgrade them and manually install everything, also tried nm-applet solution. But nothing seems to be working. The network manager icon is not there and normal reboot has no networking option. I have also gone to recovery and enabled networking via Ethernet and then resumed normal boot. But again after reboot there is not networking option. No WiFi, no Ethernet.
Can someone please help me out? Reinstalling will definitely solve this but all my settings and work will be gone and it is painful to set up again. So folks here please suggest me what to do.