The extension checks if a "Quote" button exists, and if it doesn't - creates "Quote to clipboard". So now obviously all posts in locked threads have "Quote" buttons and this no longer works. I'll think of something else. I can either use some other way to determine if the thread is locked, or perhaps inject the "Quote to clipboard" button in all threads, even unlocked ones.
Thanks for quick reply.
Adding Quote to clipboard button for all threads is probably easier for next update, just think of some shorter name for the button.
We have much more active forum software developer now so I think we can expect more forum code changes in future.