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Firefox can fail to spawn child processes on the first launch. After being restarted it runs fine. Consider adding more swap space for stable Firefox work.
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In some scenarios Firefox hangs or crashes. In many cases enlarging the swap helps. In the example below we enlarge swap from 4 to 8 GB:
$ zfs get volsize rpool/swap
NAME PROPERTY VALUE SOURCE
rpool/swap volsize 4G local
$ pfexec zfs set volsize=8g rpool/swap
$ pfexec reboot
Desktop software and libraries
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