Twitter is having difficulties holding on to its most active users, a new report suggests.

An internal document written by a Twitter researcher and seen by Reuters said that “heavy tweeters” have been in “absolute decline” on the platform since the start of the COVID-19 pandemic in early 2020.

The surprise news of Twitter’s battle to retain its most devoted users comes in the same week that billionaire entrepreneur Elon Musk is expected to finally seal a $44 billion deal in a controversial takeover of the social media platform.

Titled, “Where did the tweeters go?”, the document defines a “heavy tweeter” as a person who opens Twitter almost every day and posts content three or four times a week. Such users generate 90% of all the posts that land on the service, despite accounting for less than 10% of its monthly users.

Interestingly, the document also suggests that the kind of content that heavy users like to view on Twitter is also changing.

It said that many of these users appear to be moving away from traditionally popular subjects such as news, sport, and entertainment in favor of cryptocurrency (though this has declined to some extent since the currencies nosedived a few months back) and not-safe-for-work content such as pornography.

As the news outlet points out in its report, a shift toward such subjects has the potential to narrow the field of advertisers willing to associate itself with such content, which could potentially impact Twitter’s bottom line.

However, the document failed to offer a reason as to why Twitter’s heavy users appear to be on the decline.

Twitter is currently going through a tumultuous period, with a degree of uncertainty over the direction that the platform will take once Musk takes ownership.

There are fears that Musk plans to lay off around three-quarters of its workforce, a move that would leave just 2,000 people to run the operation for some 238 million daily users around the world.

Musk has also said that he would like to relax Twitter’s content moderation policies, a move that some are concerned will lead to more misinformation and harassment on the platform.

Once Musk’s takeover deal is confirmed in just a few days’ time, it’s hoped its new owner will quickly lay out his plans for the service.