I wrote an under-100-character oneliner for getting all saved WiFi passwords on Windows 10 computer:
netsh wl sh p|%{($_-split': ')[1]}|%{$_;netsh wl sh p n=$_ k=clear|%{($_-split'nt\s+: ')[1]};''}
Ouput will be in the format:
SSID (network name)
WPA key (network password)
Each combo will be separated with an empty line. If some WiFi networks haven't got password, then only SSID will be shown.
