New briefing is up

[GoodTaste]

Does "is up" mean "emerges" here? Or does it mean "makes a debut"? Or does it mean "is up on the list, like the bestselling books"?

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Paul Krugman (Nobel laureate)
@paulkrugman
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18m
New briefing, "Oh what a lovely trade war", is up

 

[SoothingDave]

It's the topic being discussed. I think he's making a baseball reference to the topic taking its turn at bat. Then again, it's Krugman, so who knows what he's actually thinking.

 

[Skrej]

I imagine it's some kind of blog/webpage/forum thread/social media post. 'Up' can mean 'online' or 'publicly visible' in the context of the internet and websites, etc.