Hello @Jayman2000, this is expected and normal because there is no linux-compatible DLC marked in Steam's database for Half-Life Alyx. I take it you were looking for Half-Life Alyx's Workshop Tools which would require going to Steam -> Settings -> Steam Play and check the Enable Steam Play for all other titles to tell Steam to override the platform check (same as https://github.com/ValveSoftware/Proton/issues/3111).
Actually, I was not looking for Half-Life: Alyx's Workshop Tools specifically. I was mainly looking for the Index Preorder Items. Are the Index Preorder Items compatible with Linux? Are they supposed to be compatible with Linux?
I already have Steam Play enabled for all titles. I tried disabling it, restarting Steam, re-enabling it, and restarting Steam again, but there's still no DLC tab.
Your system information
Please describe your issue in as much detail as possible:
Expected result
In Half-Life: Alyx's properties window, there is a tab labeled "DLC".
Actual result
In Half-Life: Alyx's properties window, there isn't a tab labeled "DLC". Steam's command line output.
Steps for reproducing this issue: