Not sure if I am blind or it doesn't exist, but it would be great if there would be a material A/B testing icon, or something to represent this!
Just something simple like this without the colors?

Thanks for your great work!
Or like, this one:

But without the fan and change the C into a B.
Would any of these work?

Or you can go with something a little more abstract; which Material tends to do.
I think this one would be perfect

Or there is this one:

Oh I like that one too! I think either will work :D
Let the voting begin. 1st (:+1:), 2nd (:smile:), or 3rd (:heart:)?

鉂わ笍
Of those 3, my vote goes to the second but I think something similar to the "A/C" would work better.
call-split could be another option, too:
I think that could be a temporary option, though I highly prefer an actual A/B one.
The letters look kind of odd. Not sure about language conflict. In math, you use Latin and Greek symbols even if you're Chinese.
This needs to be updated to use the alpha-* letters.
I do not believe that this will be a language conflict as programming is done primarily in English.
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Let the voting begin. 1st (:+1:), 2nd (:smile:), or 3rd (:heart:)?