Is Lightroom 6 compatible with OS X Capitan?
Yes, Lightroom 6 is compatible with Mac El Capitan however, there are some known issues.
Here is the reference article : https://helpx.adobe.com/lightroom/kb/lightroom-and-el-capitan---mac-os-10-11.html
We have just released Lightroom 6.4/2015.4 which fixes the issue of Nikon tether with Lightroom running on Mac OS 10.11.
Please refer Lightroom CC 2015.4 / 6.4 now available
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