X, the social media company formerly known as Twitter, has scrapped a feature that lets users self-report political misinformation on the platform, a research group says, marking the latest safety-focused guardrail that X has rolled back since billionaire Elon Musk took the helm.

The move was first spotted by an Australia-based digital policy think tank, Reset Australia. The group of researchers sent an open letter to X warning of the potential harms this can cause as it came just weeks ahead of a major referendum vote on whether to change the Australian constitution to establish an Indigenous advisory group with a direct line to government.

"There now appears to be no channel to report electoral misinformation when discovered on your platform," the letter from Reset Australia states. "It is extremely concerning that Australians would lose the ability to report serious misinformation weeks away from a major referendum."

The rollback also comes as political campaigning for the United States 2024 presidential election ramps up, and concerns about the spread of misinformation online remains a keystone issue ahead of the US vote.

X did not immediately respond to CNN's request for comment Wednesday morning. X users, notably, can still report content on the platform for violations in other categories — such as "Hate," "Abuse & Harassment," and "Violent Speech," among other issues. Musk has also long touted the platforms "Community Notes" feature, which lets users add context they think is missing to posts.

The user-reporting feature initially launched as a test for a small group of users in the US, South Korea and Australia, X (then called Twitter) announced in August 2021. The feature allowed users to report a post as "it's misleading" when they encountered problematic political content. In January 2022, the company said it was expanding the misinformation reporting feature to more countries and users.

Musk's rocky takeover of Twitter, meanwhile, was officially completed in October 2022.

With Musk at the helm, the platform has also made other changes, such as reinstating controversial accounts, including those belonging to former US President Donald Trump and rapper Kanye West. Musk has long opined concerns about perceived censorship on the platform and its need to focus on promoting what he views as "free speech."

In other recent changes to its approach to political content, X announced last month that it will again allow political ads on the platform — for the first time since 2019 — and said that it is hiring for its safety and election teams ahead of the 2024 US presidential vote.