In fact, Bookshelf Mod 1.18.1/1.16.5/1.12.2 is extremely useful mod support that includes common codes and APIs for author mods. This is an extremely necessary mod that you should consider using in the future.
About Bookshelf mod
It is obvious that, with the support from this mod, the mod can work with other mods from other developers even that the conflict has appeared before. That is the reason why you should install this library if you have any difficulty when playing with the incompatibility of the different mod. With this mod, you will have smooth experiences when playing Minecraft.
As mentioned above, this is a support mod so it will not have any effect when the individual installed into Minecraft. The mods that are supported by it usually use the same code structure. So to reduce the file size, save more time, and optimize everything, the author merged this code into this mod. That is the reason why if you do not install this mod before it needs it, it will run and generate an error or failure to load the main menu.
In brief, the Bookshelf mod is worth for you using in the future. Like other mods, please install Minecraft Forge before you want to use this mod.
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