The bug is that the Bridge/ACR combo has started generating xmp files for some JPEGs. Here is my default usage of Bridge: I use Bridge to open RAW format files (from my DSLR/mirrorless cameras and Android phones), any Photoshop edited tifs, and the occasional original jpg from a camera/phone within the Adobe Camera RAW dialog to make non-destructive edits before bringing these "source" files into Photoshop (most of the time, I'm just using the image processor to bake out the adjustments with some final automated actions) before saving the "final" jpegs that I'll upload to my photo sharing site. In this workflow, I absolutely want ACR to open the original jpeg files...and I actually do not usually re-open the "final" ones because I don't want to have them go through an additional round of lossy compression. I've been using this technique for two decades without any problems. Image processor support is one of the reasons I still favor a Bridge based workflow to Lightroom (I also use Lightroom Mobile and Classic, but I prefer to remove my files from my Lightroom libraries and finish my edits from Bridge)...plus I prefer to manage my own libraries because I'm constantly shifting where I store my files based on where I am in my editing/finishing/archiving process. Most of the time, I'll touch the "final" jpegs to make last minute edits to metadata...things like the captions I had set in the description field, modify my copyright info URL, change the label color, etc. This is what I tend to do once I have a whole collection of images I plan to share in my online gallery...because I tend to work out the final sequencing once I have all of the "final" jpegs altogether in one place (and I'll want the captions to flow from one image to the next). Most of the time, Bridge works as expected...where metadata edits, whether made within the ACR dialog or within the metadata fields in Bridge, stay with the JPEG file. The bug that appears to have been introduced when Adobe Camera RAW 16.3 or 16.4 is installed is that, for whatever reason, Bridge starts generating .xmp files for those jpegs when I make those final edits. If I delete those .xmp files, my last minute changes to the jpegs go away. Please understand that the problem completely goes away if I reinstall Adobe Camera RAW versions 16.0, 16.1, or 16.2...and the problem comes back immediately when I update past that. This is why I am nearly 100% sure the bug has to be within Adobe Camera RAW. Rolling back only ACR is all that it took to make the problem go away...I'm still using the latest version of every other Adobe product.
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