How to set passive boost unstackable?

I’m using the skillsystem ver20201128 by FeBuilder, want to know how to set the passive booster unstackable (while hold multiple booster, only one is effective)

For vanilla, there is a patch.
However, in the case of SkillSystems, SkillSystems’ own passive booster is installed, so this cannot be used.

In that case, there is no other way than custom build.
SkillSystems’ own passive booster is written in a very esoteric, so I think it’s very hard to fix.
For more information, search for the SkillSystems source code under “prCheckItemHasPassiveStatBoosts”.

It’s hard for me to read the source code.
Anyway, thanks for your reply!