If my import contains mixed file types, like jpeg and png for instance, do I somehow need to treat these differnt file types differently in Lr or does Lr handle that for me?
Lightroom should handle everything for you. You just need to make your adjustments.
You can import all kind of files with supported file formats in Lightroom at a time.
Click to refer supported file formats in Lightroom :
Supported file formats in Lightroom
Hope this help.
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