Modernize Conda-Forge Guidance

In user and developer section.
Use miniforge, rely on mamba for solvers, avoid any use of
default (anaconda) repos for users with firewall rules (e.g., FNAL),
where even though we don't use those repos the tools error out on
the first failed query.

docs/source/install/dependencies.rst

@@ -45,27 +45,26 @@ For all other systems, we recommend to use a **package dependency manager**:
 Pick *one* of the installation methods below to install all dependencies for ImpactX development in a consistent manner.
 
 
-Conda (Linux/macOS/Windows)
----------------------------
+Conda-Forge (Linux/macOS/Windows)
+---------------------------------
 
-`Conda <https://conda.io>`__/`Mamba <https://mamba.readthedocs.io>`__ are cross-compatible, user-level package managers.
+`Conda-Forge <https://conda-forge.org/download/>`__ is a repository for cross-compatible, user-level packages.
 
 .. tip::
 
-   We recommend to configure your conda to use the faster ``libmamba`` `dependency solver <https://www.anaconda.com/blog/a-faster-conda-for-a-growing-community>`__.
+   We recommend to deactivate that conda self-activates its ``base`` environment.
+   This `avoids interference with the system and other package managers <https://collegeville.github.io/CW20/WorkshopResources/WhitePapers/huebl-working-with-multiple-pkg-mgrs.pdf>`__.
 
    .. code-block:: bash
 
-      conda update -y -n base conda
-      conda install -y -n base conda-libmamba-solver
-      conda config --set solver libmamba
+      conda config --set auto_activate_base false
 
-   We recommend to deactivate that conda self-activates its ``base`` environment.
-   This `avoids interference with the system and other package managers <https://collegeville.github.io/CW20/WorkshopResources/WhitePapers/huebl-working-with-multiple-pkg-mgrs.pdf>`__.
+   In order to make sure that the conda configuration uses ``conda-forge`` as the only channel, which will help avoid issues with blocked ``defaults`` or ``anaconda`` repositories, please set the following configurations:
 
    .. code-block:: bash
 
-      conda config --set auto_activate_base false
+      conda config --add channels conda-forge
+      conda config --set channel_priority strict
 
 .. tab-set::
 

docs/source/install/users.rst

@@ -37,36 +37,35 @@ If want to use ImpactX on a specific high-performance computing (HPC) systems, j
 
    .. image:: conda.svg
 
-Using the Conda Package
------------------------
+Using the Conda-Forge Package
+-----------------------------
 
-A package for ImpactX is available via the `Conda <https://conda.io>`_ package manager.
+A package for ImpactX is available via `Conda-Forge <https://conda-forge.org/download/>`__.
 
 .. tip::
 
-   We recommend to configure your conda to use the faster ``libmamba`` `dependency solver <https://www.anaconda.com/blog/a-faster-conda-for-a-growing-community>`__.
+   We recommend to deactivate that conda self-activates its ``base`` environment.
+   This `avoids interference with the system and other package managers <https://collegeville.github.io/CW20/WorkshopResources/WhitePapers/huebl-working-with-multiple-pkg-mgrs.pdf>`__.
 
    .. code-block:: bash
 
-      conda update -y -n base conda
-      conda install -y -n base conda-libmamba-solver
-      conda config --set solver libmamba
+      conda config --set auto_activate_base false
 
-   We recommend to deactivate that conda self-activates its ``base`` environment.
-   This `avoids interference with the system and other package managers <https://collegeville.github.io/CW20/WorkshopResources/WhitePapers/huebl-working-with-multiple-pkg-mgrs.pdf>`__.
+   In order to make sure that the conda configuration uses ``conda-forge`` as the only channel, which will help avoid issues with blocked ``defaults`` or ``anaconda`` repositories, please set the following configurations:
 
    .. code-block:: bash
 
-      conda config --set auto_activate_base false
+      conda config --add channels conda-forge
+      conda config --set channel_priority strict
 
 .. code-block:: bash
 
-   conda create -n impactx -c conda-forge impactx
-   conda activate impactx
+   mamba create -n impactx -c conda-forge impactx
+   mamba activate impactx
 
 .. note::
 
-   The ``impactx`` `conda package <https://anaconda.org/conda-forge/impactx>`__ does not yet provide GPU support.
+   The ``impactx`` package on conda-forge does not yet provide `GPU support <https://github.com/conda-forge/impactx-feedstock/issues/4>`__.
 
 
 .. _install-spack: