Whitespace in GNU Screen broken since v0.13.5

[laverdet]

$ upterm version
Upterm version v0.13.3

$ screen -dmS console bash -c 'echo -e "HELLO\n        HELLO"; exec sh'; upterm host --accept --force-command 'screen -x console' -- sh 

=== OM6RX4ECFE8OVQ9FFNI8                                                                                                 
Command:                sh                                                                                              
Force Command:          screen -x console                                                                               
Host:                   ssh://uptermd.upterm.dev:22                                                                     
Authorized Keys:        n/a                                                                                             
SSH Session:            ssh om6Rx4Ecfe8OvQ9fFni8:[...]=@uptermd.upterm.dev

sh-3.2$ ssh om6Rx4Ecfe8OvQ9fFni8:[...]=@uptermd.upterm.dev

HELLO   
        HELLO
sh-3.2$ 

$ upterm version
Upterm version v0.13.5

$ screen -dmS console bash -c 'echo -e "HELLO\n        HELLO"; exec sh'; upterm host --accept --force-command 'screen -x console' -- sh 

=== 2XLOIYHKYZPZ6QFIKTFH                                                                                                 
Command:                sh                                                                                              
Force Command:          screen -x console                                                                               
Host:                   ssh://uptermd.upterm.dev:22                                                                     
Authorized Keys:        n/a                                                                                             
SSH Session:            ssh 2XLoIYhkYZPZ6QfIKtfh:[...]=@uptermd.upterm.dev

sh-3.2$ ssh 2XLoIYhkYZPZ6QfIKtfh:[...]=@uptermd.upterm.dev

HELLO   
HELLO
sh-3.2$ 

It looks like that release was only upstream dependencies so something else broken along the way. It's broken in the same way on the latest v14.3.0.