The bug
Map data from exploring a region is lost after zooming out the map using 8 paper.
This can be been seen best when the player is not in the area visible on the map.
Steps to reproduce
See attached screenshots for expected results
Craft 2 Empty maps (not copies) - e.g. a Map in Hotbar Slot 1, a Map in Hotbar Slot 2.
Use the Map in Hotbar Slot 1
Use the Map in Hotbar Slot 2.
Observe map data shown is identical for both maps. In the attached example, note for reference the village shown on the map.
Zoom out Map in Hotbar Slot 1 using 8 paper. Look at Map and observe map data is present.
Travel straight 300 blocks on X axis and 145 blocks on Y axis.
Observe that on both maps the player's location is shown as a white dot along the edge, indicating the player is outside of the maps' boundaries
Zoom out Map in Hotbar Slot 2 using 8 paper. Look at Map and observe map data is missing. EXPECTED: Explored section remains visible.
Return to original location. Observe that previously explored map data shown on this map reappears on Map in Slot 2.
Attachments
Comments 4
Happens also while you are in the area the map displays but might be harder to notice since the area around you instantly appears on the map.
@Marcono1234
Just verified your statement. The explored map always does disappear. I expected about 1/4 of the zoomed out map that was previously explored to remain explored after zooming out.
(This wasn't too noticeable to me due to the player's large radius for uncovering an unexplored map, But when zooming to the final zoom step it becomes evident.)
Note regarding the severity: I spent many hours fully exploring a map and it was the opposite of fun to find out all that exploration was a waste and the info lost after zooming out the map. I'm sure I'm not the only player to encounter this.