---- key quote from the above discussion ----
We asked how to collaborate with them.
Their replied as following:
"It's interesting what you guys do and let's keep in touch. I'm not really quite sure right away in regards to what can be imported to the main branch, but hopefully we'll find things to collaborate on. We're a bit busy towards the end of the year, so probably a good idea to catch up in January."
More than two months have passed. We are still waiting for their requests. We are very confused ...
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Seems reasonable to me. These people are running one of the largest websites out there, the project is open source, they seem to have put a reasonable effort into merging the changes back in, they were ignored. They could have just kept the changes internally but they decided to share. Good for them!