3rd party content appearing as character options despite only core rules enabled

As the title says, I just walked through session 0 character creation with players and many of them chose a weapon mastery option for an "atgeir" which I'd never heard of before.

Turns out it's from a 3rd party add on book, but in character creation if I disable all source books excep 5.5e core, the weapon mastery options still exist. This is really frustrating because new players couldn't possibly know what weapons are/are not included in the regular game and if it's an option to select, they should be able to play with it.

Having a visible option that's actually not owned and behind a paywall, with no way of disabling it is very frustrating. I hope this can be sorted out, because now I have to chat to all my players and keep an eye on all their character options because DnDBeyond can't actually restrict content based on what I am sharing with them.

Disabling sources under the campaign's "Content Management" when Content Sharing is enabled does not prevent character sheet options appearing, it just means the players won't be able to read the compendium unless they own it or have it shared with them in a different campaign that has it enabled.

You have two options:

Your or the player can edit character and uncheck Kobold Press under Partnered Content which will prevent things from that publisher appearing in the sheet. They can do this for most sources.

Players can click the item and see "source" to see what book it is from and only add if it is from a book you have approved. 

Yeah, between the DM and I we have access to nearly everything and have this issue.  

I understand that they are working to upgrade that functionality as we speak.

Your or the player can edit character and uncheck Kobold Press under Partnered Content which will prevent things from that publisher appearing in the sheet. They can do this for most sources.

Yep that's exactly what I did. I disabled everything on the characters sheet except 5.5e core rules and it still showed locked/paywalled content, which is really frustrating and why I made this post. thanks for the reply though

Players can click the item and see "source" to see what book it is from and only add if it is from a book you have approved. 

This doesn't work when the player is building a character and an item is listed as a mastery option. It doesn't show where the item is sourced from. It took my searching in DnDbeyond to find that it's paywalled.