I thought so too at first as I'm aware Fedora has a more restrictive security guideline. I installed firewalld and did according to the provided manual. It's different now, but still nothing works:

(base) [user@f30 fabric-samples]$ cd test-network/
(base) [user@f30 test-network]$ ./network.sh up
Starting nodes with CLI timeout of '5' tries and CLI delay of '3' seconds and using database 'leveldb' 

LOCAL_VERSION=2.2.0
DOCKER_IMAGE_VERSION=2.2.0
Creating network "net_test" with the default driver
Creating volume "net_orderer.example.com" with default driver
Creating volume "net_peer0.org1.example.com" with default driver
Creating volume "net_peer0.org2.example.com" with default driver
Creating peer0.org2.example.com ... done
Creating orderer.example.com    ... done
Creating peer0.org1.example.com ... done
CONTAINER ID        IMAGE                               COMMAND             CREATED             STATUS                    PORTS                              NAMES
eff58b51de11        hyperledger/fabric-peer:latest      "peer node start"   2 seconds ago       Up Less than a second     0.0.0.0:7051->7051/tcp             peer0.org1.example.com
f610d2bca29e        hyperledger/fabric-peer:latest      "peer node start"   2 seconds ago       Up Less than a second     7051/tcp, 0.0.0.0:9051->9051/tcp   peer0.org2.example.com
0eb3c219d317        hyperledger/fabric-orderer:latest   "orderer"           2 seconds ago       Up Less than a second     0.0.0.0:7050->7050/tcp             orderer.example.com
0c4437009820        ubuntu                              "bash"              15 hours ago        Exited (0) 15 hours ago                                      elated_swirles
3d15519bcfab        hello-world                         "/hello"            15 hours ago        Exited (0) 15 hours ago                                      naughty_borg
53a4e50a385d        hello-world                         "/hello"            16 hours ago        Exited (0) 16 hours ago                                      blissful_shannon
15f638ad5f95        hyperledger/fabric-peer             "peer node start"   16 hours ago        Exited (0) 16 hours ago                                      distracted_jones
(base) [user@f30 test-network]$ docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
(base) [user@f30 test-network]$ cd ..
(base) [user@f30 fabric-samples]$ cd fabcar/
(base) [user@f30 fabcar]$ ./startFabric.sh javascript
/home/user/fabric-samples/test-network /home/user/fabric-samples/fabcar
Stopping network

Removing peer0.org1.example.com ... done
Removing peer0.org2.example.com ... done
Removing orderer.example.com    ... done
Removing network net_test
Removing volume net_orderer.example.com
Removing volume net_peer0.org1.example.com
Removing volume net_peer0.org2.example.com
Removing network net_test
WARNING: Network net_test not found.
Removing volume net_peer0.org3.example.com
WARNING: Volume net_peer0.org3.example.com not found.
---- No containers available for deletion ----
---- No images available for deletion ----
(base) [user@f30 fabcar]$ docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES