Hi Christophe,
I also discussed with R&D whether removing a column from view should perhaps also remove that column’s sort setting.
If a new sorting is not defined and the system automatically removes sorting from the removed column, the system will use the default sorting. However, the user can remove from the view also the column which is defined for the default sorting. Therefore, I think that before the column is removed from the view, the user needs to remove the sorting from this column and set a new sorting on another column.
it still appears the best solution/tip is to restore all the columns and see which ones have spring defined to remove them specifically from the view as mentioned in my first reply.