Invalid filtering of "list of values" fields #3200
Description
When a map element contains a "list of values" field and the field contains the same value twice, the multi-choice filter for this field will filter the field out.
For example if element's field contains just one value e.g. "property1", the filter will accept it and the element will be shown. But if the field contains the same value twice ("property1,property1") the filter will reject it and the element will be hidden.
In the following example there are two elements in one layer. Both elements have a "feature list" field but in the first element the field contains just one value "property1", while in the second element the field contains the same value twice ("property1,property1"). So after enabling the filter the second element will be filtered out which I think is an incorrect behavior. I attach an exported project.
Before enabling the filter:
After enabling the filter:
The project:
umap_backup_untitled-map.umap.zip