When ticking the box to 'show advanced columns', any manual data mapping entries are lost. It looks like the 'automatic' mappings replace any manual ones.
FYI - Unticking the box does not bring the mappings back.
- Just in case there were two ways to save (advanced and normal), I tried putting in manual mappings when the box is ticked and then trying to save, but when reloading the app, the mappings are still lost.
Preview a bit of data:
Advanced columns removes the manual mapping!