Riccardo Argurio, Francesco Benini, Matteo Bertolini, Giovanni Galati, Pierluigi Niro2024-04-162024-04-162024-04-04https://openscience.sissa.it/handle/1963/35472Three-dimensional Yang–Mills–Chern–Simons theory has the peculiar property that its one-form symmetry defects have non-trivial braiding, namely they are charged under the same symmetry they generate, which is then anomalous. This poses a few puzzles in describing the corresponding Symmetry TFT in a four-dimensional bulk. First, the braiding between lines at the boundary seems to be ill-defined when such lines are pulled into the bulk. Second, the Symmetry TFT appears to be too trivial to allow for topological boundary conditions encoding all the different global variants. We show that both of these puzzles can be solved by including endable (tubular) surfaces in the lass of bulk topological operators one has to consider. In this way, we are able to reproduce all global variants of the theory, with their symmetries and their anomalies. We check the validity ofour proposal also against a top-down holographic realization of the same class of theories.enPreprint