Currently, we can adjust the max fps only by the step of 5. Having the ability to adjust it by 1 is much more useful. For example, it's great if you want to achieve the optimal G-Sync experience (explanation here or here).

I hope this becomes the default. FreeSync needs approx. 3 FPS lower than the refresh rate in order to work properly.
This would greatly help screen tearing.

I think if you change line 98 of src/main/java/me/jellysquid/mods/sodium/client/gui/SodiumGameOptionPages.java from .setControl(option -> new SliderControl(option, 5, 260, 5, ControlValueFormatter.fpsLimit())) to .setControl(option -> new SliderControl(option, 5, 260, 1, ControlValueFormatter.fpsLimit())) the step should become 1. It's just changing the third number to whatever you want the step to be.

It works! Thanks!
Only had to disable Sodium version check in Iris to make the game launch with self-compiled builds.

Does anyone know how to do this on the latest version? Sodium has been changed quite significantly internally and I can't find anything similar in order to change it.
It's now in src/main/java/net/caffeinemc/sodium/config/user/UserConfigCategories.java

The rejected PR contains rationale why this issue is a wontfix.

We are not going to change this behavior, since vanilla now enforces that the config values are within their defined ranges.