Comment # 3 on bug 1173907 from Moritz Rakow

Actually, I experimented a bit and found out how to open the SSID list!

Pressing down arrow reveals it.

So I guess the scan works just fine, but the UI could be made more obvious for
dumb users like me.

The little window that pops up after pressing scan only says "Obtaining essid
list", than closes. Whether this succeeded or failed is not visible in the UI
until down-arrow is pressed while the SSID field is focussed.

SSIDs, including network names with spaces in them, can be selected.

However, manually entering an SSID with spaces is not possible.

Entering spaces in the password/PSK field works fine.