I suggest to include details about previous / current partners when giving information to FamilySearch. Therefore, when on FamilySearch, someone can attach that information to the correct people. 

Here is an example: https://www.openarch.nl/gld:A0D29D97-BD8C-4E69-B879-710A72F74B36 and https://www.familysearch.org/search/linker?pal=%2Fark%3A%2F61903%2F1%3A1%3A4Q3V-7VMM&id=LWYC-YKP&hinting=%2Ftree%2Fperson%2Fdetails%2FLWYC-YKP&icid=fs-hinting. As you may see, Cornelia Hendrika Kloosterboer was the spouse of Hendrik de Weerd. However, you do not know that from the FamilySearch record as given by OpenArch.nl

Verwart u niet de door FS verfilmde BS-gegevens met een particuliere stamboom elders op de FS-site? Zie knop "return to Family Tree" op de door u aangegeven FS-link.

I think the point Jordi is trying to get across, is that there is an issue with the field mapping between Open Archives and FamilySearch.

If we look at the record in OpenArchives you'll see that the field for spouse is called (ex-)partner, because that's what the field is called at the primary data source, the Gelders Archief:

this results in the partner not being mapped in FamilySearch, as you can see here:

if you then go to Tools > Review Attachments in FamilySearch, the partner's name doesn't show as per the screenshot Jordi provided

Let me provide a second example, here you see that the record in Open Archives has a field for wife, and a field for Widower (or better widower of):

again this is based on the data OpenArchives receives from the primary data source:

if we look at this record in Family Search, you'll see that wife has mapped to Spouse's Name, and this information can be attached to a family tree in FamilySearch, but the information of the former spouse of the deceased was not mapped at all

in short, in the system integration design the field mapping has been done incompletely - for whatever reason -, and as a result FamilySearch doesn't contain the same information as OpenArchives

Ah, so it seems to be an issue with the (ex-) part. FamilySearch does not receive or use previous spouse information.