OpenTTD ingame download issue

OS: Debian 10 (Buster)
OpenTTD 1.8.0

Mobile connection via USB tethering


Task: requesting FIRS Industry Replacement Set 3
grey popup window below (ascii art):

---------------------------------------
|      Downloading content...          |
|                                      |
|    0 B of 916 KiB downloaded(0 %)    |
|         Requesting files...          |
|                                      |
|            [    Cancel     ]         |
---------------------------------------


Debug info:

~$ openttd -d net=9
dbg: [net] [core] starting network...
dbg: [net] [udp] initializing listeners
dbg: [net] [core] network online, multiplayer available
dbg: [net] Detected broadcast addresses:
dbg: [net] 0) 192.168.42.255
dbg: [net] Connecting to content.openttd.org:3978 (IPv4)
dbg: [net] [tcp] connected to 94.23.161.41:3978 (IPv4)
dbg: [net] Connecting to binaries.openttd.org:80 (IPv4)
dbg: [net] [tcp] connected to 94.23.161.41:80 (IPv4)
dbg: [net] [tcp/http] requesting binaries.openttd.org/bananas
dbg: [net] [tcp/http] downloading 106 bytes