How to run a child process inside firejail sandbox?

Hello Linux folks i need help running with firejail with a java program that is in sandbox

--private --trace java -jar program.jar

But this program can't spawn child process (chromium) due to sandbox restriction The trace error:

3: java:lstar64 /home/username/.program/101.0.4951.54/chrome-sandbox:0

3: java:access /proc/self/ns/user:0

3:java:access /proc/sys/kernel/unprivileged_userns_clone:0

3:java:open64 /proc/sys/kernel/unprivileged_userns_clone:47

If I run the program without firewall it successfully spawns the child process but when run with firejail it does not spawn it It seems I can't spawn this child process due to the restricted process using the firejail any help will be appreciated.