Technologist Andy Baio was among those who noticed the change on Twitter after performing a search using the operator “url:threads.net,” which returned no results. Typically, this search operator would pull in any tweets with links to the website specified — and there are plenty of tweets that have threads.net links now included.

In addition, a simpler search without the operator “url:” bit will return tweets that reference the threads.net website or Twitter users who are tweeting out their Threads usernames to their followers (e.g., “threads.net/@techcrunch), but didn’t seem to return direct links to discussions taking place on Threads’ platform (e.g., something like https://www.threads.net/t/CuiNy-zPbbJ/).

Others on Twitter have also noticed and tweeted about the change even prior to Baio’s post.

The timing of when the block began remains unclear as Twitter no longer responds to press inquiries following Elon Musk’s acquisition of the social network last year.

(These changes are in flux, so your mileage may vary depending on when you read this report.)

This isn’t the first time Musk’s Twitter has blocked links to a competitor’s website.

Shortly after the newsletter platform Substack launched its discussions feature, Substack Notes, Twitter began censoring those links by making the posts impossible to reply to, like, or retweet. The current Threads block does not go that far…at least not yet.

The animosity between the social media execs, Musk and Meta CEO Mark Zuckerberg, however, has heated up in recent days, with Musk earlier this month challenging Zuckerberg to a “cage match.” Over the weekend, the Twitter owner even resorted to name-calling, tweeting “Zuck is a cuck,” and crudely proposing a “literal dick measuring contest.”

Elsewhere, Twitter CEO Yaccarino has taken a less antagonistic stance, tweeting instead how Twitter traffic has been booming as of late, likely in the hopes of reassuring advertisers.

“Don’t want to leave you hanging by a thread…but Twitter, you really outdid yourselves! Last week we had our largest usage day since February,” the exec wrote. “There’s only ONE Twitter. You know it. I know it,” she added, in her not-too-subtle reference to Threads.

Her remarks follow numerous reports that implied Twitter traffic had been tanking in the days since Threads’ debut and fast rise. Citing data from web analytics firm Similarweb, CNBC reported Twitter’s web traffic had declined 5% for the first two days Threads was generally available, compared with the week prior. Additionally, Similarweb said Twitter’s web traffic was down 11% compared with the same days in 2022.

Other data seemed to support these findings, including a tweet by Cloudflare CEO Matthew Prince, whose company provides content delivery network services and protection against denial-of-service attacks, among other things.

“Twitter traffic tanking,” Prince tweeted, showing a graph of DNS rankings over time for Twitter.com where a steep decline was clearly visible.

    Twitter traffic tanking. https://t.co/KSIXqNsu40 pic.twitter.com/mLlbuXVR6r

    — Matthew Prince ???? (@eastdakota) July 9, 2023

In the face of these reports, Yaccarino’s comments about Twitter’s record usage appear questionable. Notably, the CEO didn’t share any specific metrics for comparison or even which day the traffic spiked.

Though Threads is off to a fast start, having leveraged Instagram’s social graph to quickly scale its user base and users’ social connections, the app’s long-term future is uncertain. After all, there’s typically a surge of demand for a new app that will then fizzle out when the initial experimentation phase is over. This was also seen with the open source Twitter rival Mastodon, which peaked last year with 2.5 million monthly users but has since dropped to 1.9 million as of today, per Mastodon’s website.

It’s worth noting, however, that figure is up from 1.4 million earlier this month, as Mastodon, too, has capitalized on Twitter’s troubles. In one of the oddest moves by a social media executive, Musk had decided to limit the number of readable tweets as a solution to a data-scraping problem that he himself had created by dramatically raising prices to the API used by third-party apps for data-gathering.

Zuckerberg smartly capitalized on Twitter’s floundering to rush out Threads even before its web version was fully functional and before its coming features, like a following feed and integration with ActivityPub (the networking protocol also used by Mastodon), were available. As a result, Threads grew faster than ChatGPT, topping 100 million users in just five days, while ChatGPT had taken two months to reach that scale.