As a rule, Valheim doesn’t have any official modding tools or offer official mod support. That naturally hasn’t stopped the community from making mods for the survivalbox, and apparently Iron Gate is flattered by that fact, but the studio is asking both players and mod makers to bear a few things in mind.
For one thing, the post once again affirms that mods aren’t officially supported and so cautions players using them to do so at their own risk. Additionally, the studio has asked that players making mods not charge money for doing so in the interest of preserving “the creative and open spirit of modding itself,” though it also suggests that players provide a monetary tip for modders’ efforts.
Finally, the post asks mod creators to clearly specify that their work isn’t officially supported by Iron Gate. All told, these aren’t precisely EULA levels of instructions, but they are some good things for modders and players to keep in mind.
There’s quite a long thread about the move over on Reddit, where players point out that some modders have been using Patreon to effectively sell mods behind a paywall, a very common situation in lots of modding communities in recent years. Presumably, Iron Gate’s statement is a response – and a bit of a warning – about that.