According to the JS API there is no method to update a portal item other than making your own request through the Portal REST API.
Am I right ?
The Portal API in the 4.0 of the JS API has this functionality.
I don't think it's baked into the 3.x API though. I could be wrong.
Good to know that it'll be here when we migrate to 4.0.
Looking forward to attend your presentations @ Dev Summit.
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