diff --git a/.github/workflows/test_branches.yml b/.github/workflows/test_branches.yml
index e576411a82b..90afddb06cd 100644
--- a/.github/workflows/test_branches.yml
+++ b/.github/workflows/test_branches.yml
@@ -308,8 +308,9 @@ jobs:
         conda config --remove channels defaults
         conda config --append channels nodefaults
         conda config --append channels conda-forge
+        conda install --update-deps -q -y conda=24.11.0
         # Try to install mamba
-        conda install --update-deps -q -y -n base conda-libmamba-solver conda==24.11.0 \
+        conda install --update-deps -q -y -n base conda-libmamba-solver \
             || MAMBA_FAILED=1
         if test -z "$MAMBA_FAILED"; then
             echo "*** Activating the mamba environment solver ***"