How do I convert an AVIF file to jpg on Windows 11 PC?

When trying to save an image, and the browser insists on saving it as an .avif or .webp file in the save dialog, the original file on the server is actually often a .jpg or .png or whatever which your browser is converting to .avif or .webp when saving it.  This is google trying to enforce their .webp and .avif formats upon users.  Some browsers are supporting this automatic conversion by default, and there may be no option for disabling it.  There are workarounds for it however:

1. Right click on the image and select "Open in new tab", this will expose the image URL.  If the original file format is available on the server which is often the case, you can usually see the image name, like "image.jpg", in the URL.  In this case, if the URL looks like this "https://(something).....image.jpg?(something)" or just "https://(something).....image.jpg", you can try to edit it to "https://(something).....image.jpg?+" and then hit Enter to reload the URL, and then try to download it again.  This may sometimes give you the original image format.

2. Try downloading the image using Firefox,.  If it doesn't save it in the original format by default, there is a setting where you can make it the default.  Some other browsers may have such an option too.

Just converting the downloaded .webp or .avif versions back to .jpg is not a good solution, as this means 2 x recompression of the original picture which is reducing its quality.