Nontrivial strict inclusions among right kernels
Construct an example, for an open surface over a local field, in which the right kernel of the Brauer–Manin pairing is strictly intermediate between the prime-to-residue-characteristic Brauer groups associated with a compactification and a regular model, with all three groups nonzero and pairwise distinct.
References
With the notation as above, is there an example in which $0 \neq () \neq (U){\perp} \neq ()$?
— Unramified cohomology and Brauer--Manin pairing
(2609.09127 - Krishna et al., 8 Sep 2026) in Section 8, subsection “Example 3,” Question 8.1