os-zerotier: Unable to add mulitple zerotier networks

[zachsmith]

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Describe the bug I am unable to add more than one zerotier network. After adding a second network, there is no interface available for assignment. The first network I add, I am able to assign an interface.

I have used multiple networks in the past but I am not sure what version of the plugin I was using then.

To Reproduce Steps to reproduce the behavior:

1. Make sure you have two different ZeroTier networks created in the ZeroTier portal: https://my.zerotier.com/
2. Install zerotier plugin to OPNsense
3. Make sure you have no networks configured in '/ui/zerotier' Networks tab. Delete them if you do.
4. Add and enable the first network by following the steps outlined in the plugin documentation
5. Make sure to Allow the host on the first zerotier network in ZeroTier portal.
6. Go to '/interfaces_assign.php' and assign the new zt* interface - it should be able to be done successfully.
7. Add a second ZeroTier network as in step 4.
8. Make sure to Allow the host of the second zerotier network in ZeroTier portal.
9. Go to '/interfaces_assign.php' and attempt to add the new zt* interface - no interface will appear for assignment.

Expected behavior An interface for all configured zerotier networks should be assignable

Screenshots

Relevant log files

Additional context I have tried removing all networks and re-adding. I have tried uninstalling and reinstalling the zerotier plugin. I have tried rebooting. I have upgraded OPNsense to the latest version.

Environment

OPNsense 23.10.1_2-amd64 FreeBSD 13.2-RELEASE-p7 OpenSSL 1.1.1w Licensed until 2026-10-15 AMD EPYC 3101 4-Core Processor (4 cores, 4 threads)