The Disco Elysium website has (presumably temporarily) disappeared, with the URL now leading to the above teaser image. The symbol is the star-and-antlers of this world's version of communism, as well as the Antecentennial Revolution, one of the key events in the history of Elysium.
There should be a few caveats before I crank up the specula-tron to max. Disco Elysium's success has led to various projects linked to the game being announced. First there's The Sacred and Terrible Air, a 2013 novel by Robert Kurvitz, lead designer and writer of the game, which is only available in Estonian but is now being translated into English and will be published at some point in the future (it was at one point slated for late 2020, though that was pre-pandemic and there's been no further update).
Disco Elysium is inspired by a book based on a table top RPG campaign of many years. "The Sacred and Terrible Air" written by our Lead writer & designer @RobertKurvitz will be published in English some time after the launch of the game. #WednesdayWisdom #IndieGameDev pic.twitter.com/jNC96sv6i2August 8, 2018
Then there's also the fact that a Disco Elysium TV series is in the works, though as no writer or network was attached as recently as June, this teaser probably doesn't relate to that. Finally, Disco Elysium is due to arrive on consoles at some point, and this could simply refer to that.
Those potential red herrings aside, this does look like a tease for a Disco Elysium game set during the revolution in Revachol. One more hint that supports this is multiple references to the Feld Playback Experiment. Players can visit the Feld Electrical Building in Disco Elysium, where they learn that Feld's engineers were developing a prototype computer, ultimately destroyed by the Coalition.
The weird thing there, of course, is that Disco Elysium's interface incorporates multiple references to Feld branding, with certain UI elements such as the task menu explicitly designed to resemble a Feld computer screen. The joke, on one level, is that you're playing a game about Elysium that looks like it was built in Elysium. I'm not going to go any further into the Feld rabbit-hole, other than to note that the above teaser has the Feld factory in the background, and Feld tape elements in the foreground. If anything suggests the new project is indeed a game, this is it.
Finally, and this is kinda-not-really a spoiler, certain possible endings in Disco Elysium suggest that another revolution is imminent. So while the image could be associated with the one that's already happened, and therefore a prequel, there are many other possibilities. Robert Kurvitz has talked in the past about wanting to make both an expansion for the original, and a sequel, though in no great detail. Either way, this can't come soon enough.