Can't open ONNX file on Mac OS X using OpenCV 4.9.0 from brew

So I’m compiling a Qt C++ application on both Windows and Mac, linking to local copies of OpenCV. In the case of Windows, I built the library from scratch. On the Mac, I used brew. When I try to load an ONNX file on my Windows application, it works fine. When I try to load on Mac, I get the message, ““OpenCV(4.9.0) /tmp/opencv-20240120-57354-wt6ray/opencv-4.9.0/modules/dnn/src/onnx/onnx_importer.cpp:4097: error: (-2:Unspecified error) DNN/ONNX: Build OpenCV with Protobuf to import ONNX models in function ‘readNetFromONNX’\n”
QWidget(0x0) LAUListWidget(0x600003b45680)” This is a brand new error. A month ago or perhaps two, I didn’t have a problem.

talk to whoever maintains the brew thingy. they forgot something.

idk, if you can set cmake options from brew, but try to set:


in order to build/use the presupplied 3rdparty src