Well, there exist like 100 threads meanwhile telling you the same already, even the screenshot workaround
And because everyone was re-asking the same I even had written all that info to the sticky threads at the top of this forum:
But noone actually seems to read that ... even if the thread's name says "Troubleshooting&HowTo: AddOn install/find, Read & report lua errors, keybind issues"
In this thread you'd have found the howto detect your addon folder, including this screenshot workaround too.
So in case someone else has the issue, please just have a a look at the sticky threads at the top of each forum FIRST, as most of them answer all these questions already. And after that ask if you got questions or it still does not work, but also please tell us what you did and read before, thanks.