I've recently updated to macOS Sonoma and now all my Affinity Designer files seem to open and immediately become desaturated. I've attached 2 images as an example of something I exported before the update and the same image exported after so you can clearly see the difference.
What appears to be happening is when I open an Affinity document, the colours immediately change. I can see this because the Quick Look preview before I open the file shows the original colours, but as soon as I open the document in Designer, the desaturation is applied. And its not just a preview thing because the desaturation comes out on export as well.
This also occurs for newly created documents where, if I load an image in, the colours immediately get desaturated.
Any idea what's going on here? My first though it some kind of weird colour space mismatch when updating to Sonoma.