Mine got pulled off too. Few days ago my extension got pulled of without explanation. I freaked out, didn't know why, because it was only RSS reader. I had few ideas why it could be so I start fixing them. I mentioned in summary that it is replacement of google reader, which they might not like, so I removed that from description. It was also using google caja sanitizer, so I replaced it with something else. Then there was preset of feeds so I removed them all. I was about to resubmit it next day when they sent me an email that it was removed by accident. They didn't tell why exactly.

Now that I see they are removing cryptocurrency miners it all makes sense. I use SHA1 sum to make GUID of article if it is not present or if it is too long, so that must have triggered their system to mark my RSS reader as crypto miner.