Since updated to 18.04 I noticed that my Lenovo computer now takes 1min to connect to Wifi when I'm on desktop :

$ dmesg | grep wlp
[ 5.937523] iwlwifi 0000:04:00.0 wlp4s0: renamed from wlan0
[ 7.588085] IPv6: ADDRCONF(NETDEV_UP): wlp4s0: link is not ready
[ 7.860116] IPv6: ADDRCONF(NETDEV_UP): wlp4s0: link is not ready
[ 7.949710] IPv6: ADDRCONF(NETDEV_UP): wlp4s0: link is not ready
[ 42.002254] IPv6: ADDRCONF(NETDEV_UP): wlp4s0: link is not ready
[ 42.702556] wlp4s0: authenticate with 50:64:2b:2b:4c:7d
[ 42.713124] wlp4s0: send auth to 50:64:2b:2b:4c:7d (try 1/3)
[ 42.720033] wlp4s0: authenticated
[ 42.724170] wlp4s0: associate with 50:64:2b:2b:4c:7d (try 1/3)
[ 42.730362] wlp4s0: RX AssocResp from 50:64:2b:2b:4c:7d (capab=0xc11 status=0 aid=4)
[ 42.748558] wlp4s0: associated
[ 48.824244] wlp4s0: deauthenticated from 50:64:2b:2b:4c:7d (Reason: 15=4WAY_HANDSHAKE_TIMEOUT)
[ 50.123369] wlp4s0: authenticate with 50:64:2b:2b:4c:7d
[ 50.131751] wlp4s0: send auth to 50:64:2b:2b:4c:7d (try 1/3)
[ 50.139950] wlp4s0: authenticated
[ 50.144101] wlp4s0: associate with 50:64:2b:2b:4c:7d (try 1/3)
[ 50.150062] wlp4s0: RX AssocResp from 50:64:2b:2b:4c:7d (capab=0xc11 status=0 aid=4)
[ 50.172241] wlp4s0: associated
[ 56.244668] wlp4s0: deauthenticated from 50:64:2b:2b:4c:7d (Reason: 15=4WAY_HANDSHAKE_TIMEOUT)
[ 57.906188] wlp4s0: authenticate with 50:64:2b:2b:4c:7d
[ 57.914858] wlp4s0: send auth to 50:64:2b:2b:4c:7d (try 1/3)
[ 57.923293] wlp4s0: authenticated
[ 57.924942] wlp4s0: associate with 50:64:2b:2b:4c:7d (try 1/3)
[ 57.931080] wlp4s0: RX AssocResp from 50:64:2b:2b:4c:7d (capab=0xc11 status=0 aid=4)
[ 57.959146] wlp4s0: associated
[ 58.071582] IPv6: ADDRCONF(NETDEV_CHANGE): wlp4s0: link becomes ready

I have approx. 20 devices connected on wifi and this is the only one experiencing issues. ( and the only one running Neon)
Any idea ?
Thanks

Check this link.
viewtopic.php?f=309&t=155599&p=406705&hilit=wifi#p406705