cjc2 wrote:
If you are talking about opening many images at the same time, I have no idea. If you are on a Mac, and the software (in Lr for me) tabs on all sides disappear, that was/is and issue which has been/is being worked on. I have the absolute latest versions of both, and have not had issues in quite some time. As much as I love my Macs, I don't feel they do quite as good a job vetting software releases as they did under Steve Jobs, but all things march on. Hope this was helpful.