Legacy Block Highlight

The Block Highlight settings screen opens when the H key is pressed, and from there the outline drawn around the targeted block can be changed in several ways. Players can set a custom RGB color for the outline, its opacity, and a chroma effect that cycles the color over time. The fill inside the selection has its own RGB color and opacity settings, so the outline and the fill can be tuned separately.

The mod can also highlight individual faces of a block rather than the whole block, which suits players who want to see exactly which side they are targeting. Legacy Block Highlight requires Legacy Fabric API and runs on the client alone, so servers do not need it. The code is open source under the MIT License, and the 1.0.0 file for 1.8.9 was published on 2026-03-23 as the first release.

The catalog lists 17 Game mechanics mods with Legacy Fabric files for 1.8.9, and this mod is one of them. Source code and an issue tracker are linked from the project.