The digital newsletter creation platform Substack said it is looking into reports alleging that Twitter embeds and authentication have stopped working on its site, even as users said that Substack links on Twitter were marked as possibly “unsafe.”
Substack helps users start and send digital newsletters to a list of subscribers, either for free or through a paywall.
Twitter and Substack users had raised complaints when they struggled to like or retweet Twitter posts that had Substack links. Others said that they could not add tweets to their Substack newsletters unless they took screenshots.
When clicking on a Substack newsletter link, users were shown a page discouraging them from leaving Twitter, which claimed that the Substack link “may be unsafe.”
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Furthermore, users entering the term “Substack” in Twitter search were instead shown results for the terms ‘newsletter’ instead.
Substack shared a statement from its founders on Friday, saying “any platform that benefits from writers’ and creators’ work but doesn’t give them control over their relationships will inevitably wonder how to respond to the platforms that do.”
The news comes as Twitter’s revenue from its top advertisers fell sharply in recent months following CEO Elon Musk’s $44 billion takeover.
Twitter has not yet made an official statement addressing the issue.