Geometry change is unclear

[danieldegroot2]

The area is highlighted with modify:geometry.

Achavi, changeset-map, OSMCha (adiff): Nothing else seems to be shown to explain this.
OSMHV: Shows a green segment, but does not seem to explain what it means.
Neis: Shows 1 node was changed, but does not seem to explain what exactly was changed.

(Feel free to mark issue as question and link to existing issue if one exists.); not sure where to post / look.

[mmd-osm]

Sorry, this is very off topic for Overpass API. You need to report this to the respective tools you've mentioned.
The difference is that one node was added to the way, as can be seen in the history: https://www.openstreetmap.org/way/984870435/history