Mods

you can check there how I does it: https://github.com/yanny7/StoneAge/blob/c9351e8050f6121256d587112a9f6071dbb61b11/src/main/java/com/yanny/age/stone/subscribers/BlockSubscriber.java#L57 it is working also for server side

ItemStack Capability data that you need on the client needs to be put in the share tag. Override Item#getShareTag and Item#readShareTag.

Hi I download and setup mc forge server 1.12.2 and download some mods (tinkers construct, mekanism), but in survival i cannot use this mods - I follow everythig in this tut (and some others) only did not set port forwarding (because my first instaled  1.14 server work with this, I use server only on LAN) I have forge server for 1.14 (folow same videos) and mods like xeros mini/map, corpse, just enough items, and It works perfectly. But in when I join to 1.12 server I can see mod items in creative mode, but when have some in inventory and click on crafting table they dissapear, game did not give me book at start and I cannot craft things from mod. I tried play singleplayer with these mods and works fine. This means I have some problem in server - I see server with "V" (hover - vanilla server) in mc multiplayer list. Can it be this problem? I did not find how "unset" vanilla from minecraft server. Sorry for my english I hope it is possible to understand.  

Where are you looking in the launcher? I suspect you are looking at Profiles/Installations rather than Versions

So yeah... looks like none of my questions has been answered lately. Should I give up on capabilities for now?