Export jpeg not as jpg

[CarolynBall]

I imported jpeg photos from my IPhone using a Windows 11 computer. I've made edits to the photos in Lightroom Classic and now I want to export the photos to the same folder.  When I do so, Lightroom converts them to jpg.  So now I have the old photo jpeg and an edited photo jpg. There must be a setting so that I can put them back as jpeg.  Jpg is old naming convention so I suspect there is a place I can change in Lightroom Classic Settings

[Bob Somrak]

This seems almost like a bug in LrC    As @CarolynBall screen clip of Explorer shows, there are TWO files in the same folder with the same name but with JPEG and JPG extensions.  One is the original and the other is the exported one where the OP exported to the same folder.  The file size differences are to be expected from the export.  The fact the references to industry standards say JPEG and JPG are the same is being ignored as the Operating System and LrC treat the files as two different files as they have different extensions.  The bug is LrC in the export is saying it is going to export a JPEG but it exports a JPG.  It happens on my Mac too.

[Jim Wilde]

The bug is LrC in the export is saying it is going to export a JPEG but it exports a JPG.  It happens on my Mac too.

By @Bob Somrak

Bob, I disagree with this, I don't see this as a bug. When we select "JPEG" in the Export dialog we are not explicitly selecting the file extension, but we are simply selecting the image format, after which LrC uses an appropriate valid extension (Jpg in this case, as it always has done). This is exactly the same when we select file type "TIFF" (LRC extension is Tif) or "JPEG XL" (extension is Jxl). The only "outlier" could be the new "AVIF" format where the extension is Avif (possibly because "Avi" is already taken).

I suppose someone could make a feature request to allow the user to specify the file extension when valid alternatives exist, but is that really needed?

[F. McLion]

IMHO, there's no need for that.

To me, how the OP wants to use LrC is against it's idea and principles. Of course, one can say, what the heck, simply make everything possible ... while I would also disagree with that.

[JohanElzenga]

I agree it's not needed. Let's not forget this is a very unusual complaint by somebody trying to use Lightroom in a way it is not intended. In all the years on these forums, this is the first time I've encountered a complaint about .jpg versus .jpeg as file extension. 

[Lumigraphics]

There were people in the Bridge forum complaining about jpeg v jpg in file export. Adobe actually changed it to allow choosing the file extension.