A promotion for new software called The Re-Entry App was shared at the top of some users’ Instagram feeds on Wednesday.

The notification, proposing help with “preparing for life after prison with community support”, asked users to click for early access to try the app and provide feedback.

“We’ve been exploring different ways to help close gaps faced by those in marginalised communities across our apps,” a Facebook spokeswoman said in a statement.

“This was only intended to be an internal test and we took down the notice as soon as we learned it briefly ran externally.” Facebook often experiments with service and app ideas that never materialise or morph into something else.

Chief Executive Officer Mark Zuckerberg said last June that he wanted Facebook to start “building products to advance racial justice” and Instagram has an equity team that builds “new features that respond to the needs of underserved communities”.