Ah ok.. Then your good.. there should be no untagged traffic hitting that port the way you have it setup.. Just know that if any untagged traffic does get onto that port from pfsense it would go to your default vlan on the switch.
To follow through with good practice you should limit your trunk port to those specific vlan IDs, 10,11,20 and 50.
Trunk ports will allows allow for untagged traffic, and if you do not call out what vlan untagged should be assigned to with the native vlan command then untagged traffic will go to whatever the default vlan is on the switch.
I just run a native vlan on my interface, and then run vlans on top of that. But your way is also very common. I do believe Derelict is a fan of only tagged traffic and not using any untagged traffic.
Glad you got it all sorted.. In the cisco world if your not going to run a native or untagged vlan on the interface then you would normally use general for the port and assign the tagged vlans and setup the port to only accept tagged traffic, etc. Where any untagged would go to garbage vlan ID. Lots of different ways to skin the cat ;)
Also bit of a side note with just using trunk vs limiting the vlans on the trunk port. Any other vlans you might be running on the switch - broadcast traffic could go down that port. It won't go anywhere since pfsense doesn't have any vlans setup for other IDs. But broadcast traffic would be sent down that trunk port since you have set for ALL vlans with just the trunk command. Blanket trunk commands like that are normally frowned upon. You normally limit the trunk to the specific vlans that that are ok to travel on that port.