Kudos on the wireguard implentation!! I've been testing it for several weeks now.
After making changes to any of the wireguard settings, I most often have to "re-cycle" wireguard by "disabling"\saving and "enabling"\saving from the "General" tab ... to get the changed CIDRs and settings to apply. Having a "restart\cycle" button to reapply the config would be a huge win when administrating\building or troubleshooting the wireguard service.
It would be similar to the "circling arrows" button on the "Connection Status" of OpenVPN.
If this is the wrong spot for this, I can open a ticket elsewhere if need be. I'm noob to the OPNSense reporting process.
Normally every Save button on every tab saves and restarts