WHOIS button doesn't work when User Details opened from PM buffer

Steps

1. Connect to a network
2. Open the buffer list left sidebar, select an private message (query) to an IRC nick that's online
3. Tap the user name in the top bar to open User Details screen
4. Tap WHOIS button
5. Return from this screen, select a channel with active users
6. Open the nick list right sidebar, tap a nickname to open User Details
7. Tap the WHOIS button

Expected

In both cases, the /whois is performed and the information is visible in the Status Buffer.

Actual

When tapping WHOIS on a User Details screen opened from the top bar in a PM, no /whois is performed and no output shown.

Only when opening User Details from a channel nick list does the WHOIS button function.