I've noticed that there is a config file but what does the option mean ?

The doSightChecksFlag option checks if a block is in the player's line of sight (turning it off allows you to reach blocks through walls). Servers can install this mod to force this check

The rotatePlayer option snaps the player's view to each tab's inventory. It is a bit jarring to look at, so it is disabled by default.

The excludeTab list is a collection of block id's to NOT display tabs

The includeTab list is a collection of block id's to force display tabs

The debugEnabled option prints debugging information (mostly for modpack developers, to be used when editing exclude/include lists)