I have a custom export to add the keywords to the filename which works, except it doesn't include containing keywords. Even when those keywords are listed in the Will Export window AND they are exported into the EXIF of the file. Just not into the filename. No idea why. It would be less strange if they weren't in the filename or EXIF.
Anyone have this issue?
I just tried this and observed the same symptoms. You could file a bug report in the official Adobe feedback forum: Photoshop Lightroom | Photoshop Family Customer Community . I couldn't find any previous reports of this issue.