I can’t suggest what exactly goes wrong, as I don’t see your code relates to the lightbox changes. But the issue looks like you are trying to access lightbox buttons of the locale object before scheduler initialization(.init) when there are non-accessible. You can console the scheduler.locale.labels objects before and after initialization to see the difference.
If you will run this code after initialization of the scheduler, it should work correctly:
If it won’t help and you still have the issue, could you please provide more details, or reproduce it in the demo above:
open the demo => reproduce the issue => click the “Share” button => send me the new link.
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