You can convert a JFIF file to JPG, though the two formats are nearly identical, and most software will open a JFIF file as a JPG.
You can convert Apple's HEIC files to PDF on a Mac or Windows computer using the free Convertio website.
In macOS, you can easily convert the format of images using a Quick Action in Finder or you can achieve the same thing via the Preview app, but if your daily workflow requires you to repeatedly ...
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