Update of the LHCb combination of the CKM angle $\gamma$

A combination of tree-level measurements of the CKM angle $\gamma$ at LHCb is performed. The results are obtained from time-integrated measurements of $B^{+}\to D K^{+}$, $B^{+}\to D^{*}K^{+}$, $B^{+}\to DK^{*+}$, $B^{0}\to D K^{*0}$, $B^{0}\to D K^{+}\pi^{-}$ and $B^{+}\to DK^{+}\pi^{+}\pi^{-}$ decays and time-dependent analyses of $B_{s}^{0}\to D_{s}^{\mp}K^{\pm}$ and $B^{0}\to D^{\mp}\pi^{\pm}$ decays. This combination includes new and updated results compared to the previous LHCb combination, giving a best fit value of $\gamma = 74.0^\circ$ with confidence intervals, set using a frequentist procedure, of $\gamma \in [68.2,79.0]^\circ$ at 68.3 % confidence level (CL) and $\gamma \in [61.6,83.7]^\circ$ at 95.5 % CL, where all values are modulo $180^\circ$. This gives the result \begin{align*} \gamma = (74.0^{+5.0}_{-5.8})^\circ\,, \end{align*} where the uncertainty includes both statistical and systematic contributions.