Twitch is halting a feature that lets viewers pay to promote their favorite streamers after bad actors used it to push porn and other NSFW content onto its homepage. First spotted by PC Gamer, a number of Twitch users on Twitter this week noticed that streams of porn videos were on the homepage, all featuring the caption “Promoted by the streamer’s community.” It appeared that a number of unidentified users were taking advantage of the platform’s “Boost Train” program, which boosts streamers if enough fans create a “hype train” by purchasing subscriptions and bits.

Since Twitch only rolled out the Boost Train feature to partners and affiliates, only a limited number of streamers have it enabled. It’s still unclear how the bad actors were able to access Boost Train-enabled accounts.

In an email to Engadget, a Twitch spokesperson said the Boost Train feature was paused “due to safety reasons.” Twitch would not comment on whether it identified the users who were behind pushing the offending content, or whether it had plans to bring Boost Train back. 

While sexually explicit content is against Twitch’s terms of service, some critics say the platform has been inconsistent about the kind of NSFW content it bans. The platform relies on a mix of community reports and AI to identify sexually explicit streams. Dot Esports this week reported that Twitch is considering a “mature label”, which would allow streamers to experiment with more R-rated content — though it’s still drawing a hard line on broadcasting masturbation or sexual intercouse.

Boost Train debuted just this month, replacing a widely-scorned “Paid Boosts” program that let fans pay Twitch directly to boost their favorite streamers. Boost Train, on the other hand, was aimed at rewarding smaller streamers with a growing fanbase.