According to a rumor on WinFuture, GoPro is readying a Hero 12 Black for mid September but, despite recent competition from DJI, it looks like GoPro will be sticking with the existing 1/1.9-inch image sensor, used in the GoPro Hero11 Black, capable of 27-megapixel photos and 5.3K video.
That's a significant drop back in size terms from the 1-inch image sensor which we've heard about from other sources, and would leave DJI the leading action camera in terms of sensor size and, one might assume, low-light capability.
The WinFuture article we read, translated from German, did indicate that the new GoPro Hero 12 Black would come in at €449.99 (about $488, £383 or AU$760) with improvements to the software stabilization called 'HyperSmooth 6.0' but otherwise no significant enhancements. We expect the new flagship model to be launched sometime in September (as has become the yearly ritual).
The only spec-sheet change which was noticed by WinFuture was to the battery life, which increased from 137 minutes to 2.5 hours (150 mins). Given the battery is still stated as 1720mAh we might, however, be looking at a different approach to rounding in a newer spec sheet (and one which isn't even final!)
If these are the final specs, they put a lot of rumors in the dust. Not only were larger image sensors mooted, to compete with the new DJI Osmo Action 4, but some spoke of new edge-to-edge designs for the 2.27-inch and 1.4-inch displays which, again, appear to be going unchanged.
If you're looking for a top-end action camera, we'd strongly suggest reading our reviews of both the GoPro Hero 11 and the new DJI Osmo Action 4; the latter has the larger image sensor so has more merit in low light, but both have reason to appear highly in our best action camera guide.