Most multiplayer servers allow Fullbright because it provides a visual convenience rather than a game-breaking advantage. How to Install Fullbright 1.12.2
While specifically optimized for version 1.12.2 , many variants of this pack are compatible across multiple versions, from older 1.7 releases to modern 1.21 updates. new fullbright 1122 resource pack
The Ultimate Guide to the New Fullbright 1.12.2 Resource Pack new fullbright 1122 resource pack