Trying to use function ppc_stat_grouped() on data including NAs

Hello everyone,

I would like to use the function ppc_stat_grouped() on data that includes NAs.

model_subj_shift_brm %>% posterior_predict(draws = 5) %>% ppc_stat_grouped(y = df_all_subjects$answer, group = df_all_subjects$diagnosis, stat = "median")

I get the following error:
Error: NAs not allowed in 'y'.

I tried deleting NAs in that column:
model_subj_shift_brm %>% posterior_predict(draws = 5) %>% ppc_stat_grouped(y = na.omit(df_all_subjects$answer), group = df_all_subjects$diagnosis, stat = "median")

I get the following error message:
Error: 'y' must be a vector or 1D array.

Thank you for any advice on how to run this function.
Juliane

Reproduce the supplied posterior_predict() and ppc_stat_grouped() calls with the NA-containing data, then inspect the ppc_stat_grouped() input validation and grouping behavior. No source files or tests are named; done would require a decided, tested behavior for missing values or a clear explanation of the supported input requirements.