A pre-release of PyMOL 2.5 may be available from Schrödinger's Anaconda channel with the alpha label.
Such an experiment is best done in a new environment (optional):
conda create -n pymolalpha conda activate pymolalpha
Install PyMOL 2.5 (note that both schrodinger/label/alpha and schrodinger channels are needed):
conda install -c schrodinger -c conda-forge schrodinger/label/alpha::pymol=2.5
See also https://pymol.org/conda/
(See Release Notes)
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