The site shut down last week, without explanation, and hasn’t returned. Its Facebook page has also disappeared.
TVAddons hosted Exodus, and there are fears that it could stop working in the future.
That would be a huge blow to Kodi users, as Exodus is one of the most popular add-ons available, providing access to a huge number of TV shows and films.
TVAddons listed a staggering 1,500 add-ons, according to TorrentFreak.
Earlier this month, it was sued by US satellite provider Dish Network for copyright infringement.
Whether the apparent shutdown proves to be permanent or temporary remains to be seen, and TVAddons is yet to explain what exactly is going on.
Kodi is a hot topic at the moment, and has come under under scrutiny from legal authorities and broadcasters.
Kodi itself isn’t illegal, but third-party add-ons built by developers can enable users to illegally access copyrighted content through it.
In April, the EU Court of Justice (ECJ) ruled that the sale of media players deliberately pre-loaded with links to copyrighted content is illegal. Crucially, it also declared that using a media player to stream copyrighted content is also illegal.
The verdict spread fear through the Kodi community, and has led to the closure of a multitude of add-ons, including Phoenix and Navi-X.
Sellers of so-called “fully loaded” Kodi boxes are being blamed for the crackdown, and have variously been described as “leeches” and “a real problem for users”.