How can I get NSSavePanel to use the extension ".jpg" instead of ".jpeg" in my app's save window? My NSDocument subclass can export images and over the years I've gotten tons of requests for the extension for JPEG images to default to ".jpg" in the save window. I'm not sure how to make this happen though - I can't change the UTType at runtime, so the preferredFilenameExtension would return something other than ".jpeg", and NSSavePanel doesn't seem to send the right messages to my document for me to influence it. Yet, I know it can be done because Preview.app uses ".jpg" as its default extension when choosing the "JPEG" format. What's the magic I'm missing?

I've got an app (Acorn) which uses a NSDocument subclass to manage the reading and writing of a number of different formats. I've always had my own Format popup in the Save window as an accessory to manage what file format the user would like to save as. But now in Ventura 13.1b2, there's an additional "File Format" being added above mine, so now there's effectively two different ways to select a format for the document to save as. And this also happens for previous versions of my app that are no longer maintained. What can I do about this, other than filing a bug report? (FB11776299)