In Lightroom 6's map module, the option in right-click map menu of "Set all to the same GPS coordinates" is always disabled/grayed out. This issue has existed for a long time, but I do remember it working in early 6.x releases. I am using Lightroom 6.13 perpetual license. Reinstalling / clean install does not fix this issue, I have tried. Attached is a screenshot demonstrating the problem.