LinusOnTheLine on "[Plugin: Import any XML or CSV File to WordPress] Strange error with some attributes"

I have some product attributes that are named in swedish which, sometimes, gives me some strange bugs/errors.
The import is set to create and update products and leave some fields alone since the attribute data can be quite different for the different products. That is "update and write as you wish but leave these fields alone".
Now to the bug. For example, let's say you have an attribute named Smörgås (smorgas as slug), which means sandwich btw, and you have a value you want to put here, for example "nom nom". Some of these values are just fine, but sometimes it makes a strange copy of the attribute. It correctly updates the "Smörgås" with "nom nom" and creates a attribute named "Sm" with the same value ("nom nom") and automatically sets this to "view on product page". This option is "idle", but if you manually make a change to a product and forget to uncheck this checkbox, it will be visible when you update. Since the import runs every hour, it can be really frustrating.
Has anyone else seen this kind of error, and how did you in that case solve it?

https://wordpress.org/plugins/wp-all-import/