I am having an issue with the Multiselect as well as Listbox modules.
The values to be displayed are queried from a external resource and change dynamically.
When checking these manually, all the desired entries appear to be returned correctly, and hovering over the input data shows all values.
In the displayed Multiselect element though, every few entries are just blank.
It also does not appear to be related to the symbols contained in the values, which are strings only.
Tested on Firefox 91.0.2 and Chrome 92.0.4515.159 on Ubuntu 20.04.3 LTS