Problem with combobox

I create one combobox that I list the data on my Db

myCombo.setItens(myDataRepository.findAll());

But when I try to use my app in a slow connection sometimes my combo lost all data just like the imagens

when I run in localhost works fine, but when I try to run in my server, or when I change the connection speed on browser devtools, and I try to insert some values randomly, the combobox lost all data and show a empty list

tks

37902.png
37903.png

Might be related to https://github.com/vaadin/framework/issues/9915.