Many threads on the issue of editing files in PS by using the "Edit In" functionality of lightroom. We know we can't open the files, at least not without waiting.
In the context of my workflow, using raw with DNG in LR. Normally when cross editing in PS there is no target file generated until we hit save. If we cancel there is no file generated at all (except maybe in cache or memory). Thus it appears I am editing directly in the DNG when it opens in photoshop.
The latest updates however immediately generate a target file, for me this is a tiff file. Worse, that file remains on the disk and appears to be the one we are editing in PS when it eventually opens up. Even if we don't save that tiff will appear in the stack. This is very damaging in terms of space and the collection.
Should be pretty easy to reporoduce. Good luck!