Docker build stopped when installing the ib-gateway 980

[bubersome]

"""
n

is invalid.
Where should IB Gateway 980 be installed?
[/root/Jts/ibgateway/980]
The directory:

"""
Nothing changed in the dockerfile.
This is the error message. How to debug this?
Thank you.

[kaminsod]

I made a fork (and PR), which works with v980: https://github.com/kaminsod/ib-gateway-docker