Enter all commands from junos CLI

Disable MLD/IGMP Snooping

set protocols mld-snooping vlan all disable
set protocols igmp-snooping vlan all disable

Change IC to 1G

set chassis fpc 0 pic 1 sfpplus pic-mode 1g

Set Password

set system root-authentication plain-text-password
enter Freifunk

Save config

commit