That fork happened already because there is a repository on smalltalkhub [1]. Lately I needed crypto support for a project of mine and I was searching for the last thing I could use. I was glad I've found the package Esteban did so I could use it in pharo. But I didn't know it was only the very last version that worked on pharo. But my Metacello setup somehow decided to load the second recent package which rendered my image unusable. From then I know that there are a lot of classes that have been incorporated in pharo which are present in the Cryptography package. I was asking for someone that maintains it and got no response.
It is clear to me that there is no easy way to maintain the package for both squeak and pharo. At least not while having one big package to share. It would need a bit of engineering. Then I remembered I was asking a similar question (about splitting the Cryptography package) years ago and I didn't get much positive resonance. Btw. this was my general feeling with the squeak community back then and the same reason I was one of the first being on the pharo train (sapphire back then).
To make a long story short. I really like spending some time for the smalltalk community. And I'm afraid I could kill my time and my mood while trying to get an agreement for something both squeak and pharo. So my current strategy is to care less and look (selfishly) forward. Maybe the better way is that each side has a look at the repository of the others and merges what is needed.
Why github? Because I want a reliable repository where my business process runs on. Smalltalkhub is close to its final growth. And my impression is that if we would put the load from smalltalkhub onto squeaksource the only thing we would notice is a bright flash and silence after.
Furthermore after all those years it turns out that you have a hard time of you do version your stuff and you want versioning to work reliable. What really works for me is having a github repo, a BaselineOf my project and tags on commits. Anything else just does not work and/or is not reproducible.
Norbert