I have a multisite installation with 3 site /fr/, /en/, /es/
I have installed MLS.
I created a category 'Sonar' in the 3 sites and linked them via MLS.
I create a sub-category 'Sonar 360' below the 'Sonar' except for the /fr/ site (my error).
I created a post affected to this 'Sonar 360' category for /en/, /es/ site and linking them thru MLS.
When it came to the /fr/ post, I did realize my previous error and that the 'Sonar 360' was not under 'Sonar'.
I did this change but now, when I affect this post to 'Sonar 360', it does not appear under 'Sonar' in the 'Categories' widget.
I put the post on 'Uncategorized', 'Sonar 360' appears below 'Sonar' as a sub-category.
If I put it again on 'Sonar 360', it becomes again a category of its own.
I can repeat it many times: post -> Uncategorized =A 'Sonar 360' = sub-category then post -> Sonar 360 => 'Sonar 360' = Category.
I suppressed the 'Sonar 360' into the /fr/ site and recreated: no change.
I suppressed the 'Sonar 360' into the 3 sites and recreated: no change.
I suppose I will have to make some update into a table to correct it (it looks a problem of relation between the post and the category).
Do not hesitate to ask for any precision.