Mod compatibility

Containers and equipment

Vanilla bundles and shulker boxes count their contents, including nested containers. Modded items that store their contents in Minecraft’s standard CONTAINER or BUNDLE_CONTENTS item components can use the same support.

Custom backpack inventories and additional equipment slots are not automatically included. Test the actual item and slot rather than assuming a backpack or accessory is counted.

Mod authors can register extra inventories or custom container contents through the API. Contents must be counted through one route; reporting the same storage twice gives the wrong total. HI receives the server’s final carried weight even when a custom container’s contents aren’t available for a client tooltip.

To check a container, compare your carried total with it empty and filled. Move items between the container and your main inventory; the contents’ weight should remain accounted for. Also check its tooltip after reconnecting and after a datapack reload.

Recipes

Ordinary fixed-output recipes can supply inferred weights. Custom recipe types, outputs that depend on item components, and recipes with crafting remainders may need explicit definitions. Use a weight report to find items receiving the fallback.

An item definition covers the item ID. It does not provide separate base weights for individual variants based on components.

HUD overlap

Two mods can draw at the same position without either one crashing. Mod authors can use HUD integration to move, hide, decorate, or replace HI’s ring and numbers. HI doesn’t automatically detect overlaps or reposition unrelated HUD elements.

Players can choose a registered owner separately for the ring and readout in client settings. If an integration fails or a selected owner is unavailable, HI falls back to its built-in display. See display and tooltips for those controls.

Movement and flight

Test movement mods alongside the penalties your pack enables. Check walking, sprinting, jumping, fluid movement, falls, and elytra flight at light load, 90% capacity, and above capacity.

Heavy Inventories preserves normal fall protection, adds its knockback bonus alongside existing resistance, and leaves currents and bubble-column motion intact. Those behaviors do not establish compatibility with every mod that changes the same actions.

There is no verified compatibility list for third-party backpack or movement mods. If you find a conflict, include both mod versions, the affected item or action, your settings, and a small reproduction in an issue .