Comment by xnyan
>...but you have to share it specifically with each separate group
For me personally, this is a feature not a bug. I want things I see to be things that somebody wrote just for that channel. It's why I use group chat over social media.
Facebook had and still has visibility options, but as it grew in features people forgot about it. A lesson in discoverability and product complexity.
https://www.facebook.com/help/233739099984085/