Not long ago, LetsGoDigital leaked a set of images purported to have come from a patent filed by OPPO for its own take on the foldable smartphone. This material did have apparent patent documents (from a Chinese intellectual property office SIPO) to back it up, and looked convincingly well-designed. On the other hand, the "OPPO foldable" device's display was not completely full-screen, as it had insertions within it for what look like multiple punch-hole cameras.
However, if a new report from the same outlet is to be believed, OPPO has since filed further patent documents (with the World IPO this time) that address this issue. They have also been converted into 3D renders, giving an indication of what they may look like in real life.
They show a foldable device with a slight bulge in one 'leaf' of the screen. It accomodates a pop-up module, which in turn houses cameras and possible other sensors. Therefore, the display is more edge-to-edge compared to its apparent predecessors.
OPPO is no stranger to the pop-up module, and has even engineered versions that are more unique compared to the usual square modules pioneered by Vivo. However, the idea of combining such a component with foldable tech may be a little bit unfeasible at this point. It would certainly increase the potentially delicate moving-part quotient, and affect bulk in this form factor.
On the other hand, the pop-up module here has tapered edges and a corresponding divot on the opposing half of the render. Therefore, it may just be possible that OPPO will have something on Samsung and Huawei when its own foldable device makes it to the market.