anova misses sometimes bottomnote

[FlorianSeitz]

data(nosofsky1989long)
DT <- as.data.table(nosofsky1989long)
DT <- DT[condition == "size", ]
DT <- DT[!is.na(true_cat), ]

model1 <- gcm(
formula = response ~ angle + size,
class = ~true_cat,
data = D,
fix = list(r = 1, q = 1), # <= fixing constraints
choicerule = "none"
)

model2 <- gcm(
formula = response ~ angle + size,
class = ~true_cat,
data = D,
fix = list(r = 2, q = 2), # <= fixing constraints
choicerule = "none"
)

anova(model1, model2)
gives me the following error:
Error in structure(tab, heading = c("Analysis of Fit Table\n", header, :
object 'bottomnote' not found