Does the latest version fix the grey "edit filter settings" when save on version 5.1.6? ?

edit

ODF documents don't have any configurable "filter settings", thus the checkbox is grayed when you select this, unlike with e.g. "Text - Choose Encoding (.txt)", where there are such settings defined; or the CSV (another foreign file format, which was discussed in the topic you linked to in your question). It's unclear from where did you take the idea that ODF should have the checkbox enabled.

The filter options are meant for those cases when the format itself isn't capable of storing essential information about itself (like encoding), and users are required sometimes to set the information explicitly. It's not the case with LibreOffice's own native ODF formats.