Stuttering of keyboard entry caused by Karabiner?

[prize-goof]

The issue is simple - turning on Karabiner causes some small but very noticeable stuttering when typing text:

Steps to reproduce:

Version: 14.13.0 on apple silicon.

1. Set a ~2000 line config.json file. Set several complex modification rules which are conditional upon the frontmost app (I do not know if this is relevant).
2. Open karabiner and check that the modifications work.
3. Now open any text editor. Quickly type some string, for example, "ababababababa". You do not need to type super fast - just the average typing speed. For every ~40 characters typed, I notice some stutter - a significant delay in the characters appearing the screen. The stutter quickly goes away but returns every ~40 characters.
4. Now quit karabiner and repeat the experiment. The stutter goes away.

Has anyone noticed similar issues? It seems like a pretty important issue but I have not found any discussion here about it.