MC-12942118w16a Game Crashes 18w19b Snapshot
I started the map in question, in 1.12.2, then converted to 18w10a. It has successfully worked through 18w16a. I didn't try it with 18w19a, because I tried a test world first, and that was a MESS. When 18w19b came out just a bit later, I tested it, and it seemed to be working OK. However, it will not load my "Are We There Yet?" map (the one in question). Upon trying to open a copy of it, it hangs and never gets past this screen (See attached MC-18w19b-TryingToStart18w16aMap.png) (that was with a modified Soartex Fanver resource pack in place).
So I started testing in Vanilla, as follows:
(1) With vs. 1.12.2, I made a map named "Testing-18w19b-Starting:1.12.2" (Spawns in a Jungle)
(2) With vs. 18w16a, I made a map named "Testing-18w19b-Starting:18w16a" (Spawns in a Taiga)
(3) With vs. 18w19b, I made a map named "Testing-18w19b-Starting:18w19b" (Spawns in a Taiga)
(4) With vs. 18w16a, I opened a copy of "Testing-18w19b-Starting:1.12.2" and renamed it to "Testing-18w19b-1.12.2To18216a" (It opened correctly, in a Jungle.)
NOTE: I did not play or develop any of those maps in any way.
(5) With vs. 18w19b, I opened a copy of "Testing-18w19b-Starting:1.12.2" (It opened correctly, in a Jungle.)
(6) With vs. 18w19b, I opened a copy of "Testing-18w19b-Starting:18w16a" (It opened correctly, in a Taiga.)
(7) With vs. 18w19b, I opened a copy of "Testing -18w19b-1.12.2To18w16a" (It opened correctly, in a Jungle.)
(8) Seeing that all of these worked correctly, in Vanilla, I made a copy of my "Are We There Yet?" map, that was started in 1.12.2, played & developed somewhat, then changed to 18w10a, played & developed more, then opened, played, & developed in 18w16a. There had been some slight problems getting it to go from 1.12.2 to 18w10a, but from 18w10a to 18w16a, there were no problems whatsoever.
In Vanilla, it DID open with 18w19b. However, it began by "Preparing Spawn Area," THEN "Loading Terrain." Sure enough...all development was totally gone. It did seem to read the hybrid mix of the seed in 1.12.2 and 18w10a, but none of the development of mineshafts and villages, or any terraforming that had been done.
So...unless something drastically changes, I won't be able to take my "Are We There Yet?" map into 1.13. 
Environment
System Information
------------------
Time of this report: 5/9/2018, 22:26:52
Machine name: LINDA-7PROPC
Operating System: Windows 7 Professional 64-bit (6.1, Build 7601) Service Pack 1 (7601.win7sp1_ldr_escrow.180422-1430)
Language: English (Regional Setting: English)
System Manufacturer: Dell Inc.
System Model: Inspiron 3650
BIOS: BIOS Date: 12/07/17 21:58:28 Ver: 05.0000B
Processor: Intel(R) Core(TM) i7-6700 CPU @ 3.40GHz (8 CPUs), ~3.4GHz
Memory: 16384MB RAM
Available OS Memory: 16328MB RAM
Page File: 7285MB used, 25367MB available
Windows Dir: C:\Windows
DirectX Version: DirectX 11
DX Setup Parameters: Not found
User DPI Setting: 120 DPI (125 percent)
System DPI Setting: 96 DPI (100 percent)
DWM DPI Scaling: Disabled
DxDiag Version: 6.01.7601.17514 64bit Unicode
(Full Report Attached)
Java 8 Update 171 (64-bit), 04/19/2010
Java 8.0.1710.11
The game, however, is set to "Use Java Bundled Runtime."
The JVM Argument line says: -Xmx2G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
Linked Issues
Created Issue:
18w16a Game Crashes 18w19b Snapshot
I started the map in question, in 1.12.2, then converted to 18w10a. It has successfully worked through 18w16a. I didn't try it with 18w19a, because I tried a test world first, and that was a MESS. When 18w19b came out just a bit later, I tested it, and it seemed to be working OK. However, it will not load my "Are We There Yet?" map (the one in question). Upon trying to open a copy of it, it hangs and never gets past this screen (See attached
MC-18w19b-TryingToStart18w16aMap.png) (that was with a modified Soartex Fanver resource pack in place).So I started testing in Vanilla, as follows:
(1) With vs. 1.12.2, I made a map named "Testing-18w19b-Starting:1.12.2" (Spawns in a Jungle)
(2) With vs. 18w16a, I made a map named "Testing-18w19b-Starting:18w16a" (Spawns in a Taiga)
(3) With vs. 18w19b, I made a map named "Testing-18w19b-Starting:18w19b" (Spawns in a Taiga)
(4) With vs. 18w16a, I opened a copy of "Testing-18w19b-Starting:1.12.2" and renamed it to "Testing-18w19b-1.12.2To18216a" (It opened correctly, in a Jungle.)
NOTE: I did not play or develop any of those maps in any way.
(5) With vs. 18w19b, I opened a copy of "Testing-18w19b-Starting:1.12.2" (It opened correctly, in a Jungle.)
(6) With vs. 18w19b, I opened a copy of "Testing-18w19b-Starting:18w16a" (It opened correctly, in a Taiga.)
(7) With vs. 18w19b, I opened a copy of "Testing -18w19b-1.12.2To18w16a" (It opened correctly, in a Jungle.)
(8) Seeing that all of these worked correctly, in Vanilla, I made a copy of my "Are We There Yet?" map, that was started in 1.12.2, played & developed somewhat, then changed to 18w10a, played & developed more, then opened, played, & developed in 18w16a. There had been some slight problems getting it to go from 1.12.2 to 18w10a, but from 18w10a to 18w16a, there were no problems whatsoever.
In Vanilla, it DID open with 18w19b. However, it began by "Preparing Spawn Area," THEN "Loading Terrain." Sure enough...all development was totally gone. It did seem to read the hybrid mix of the seed in 1.12.2 and 18w10a, but none of the development of mineshafts and villages, or any terraforming that had been done.
So...unless something drastically changes, I won't be able to take my "Are We There Yet?" map into 1.13.
Environment
System Information
------------------
Time of this report: 5/9/2018, 22:26:52
Machine name: LINDA-7PROPC
Operating System: Windows 7 Professional 64-bit (6.1, Build 7601) Service Pack 1 (7601.win7sp1_ldr_escrow.180422-1430)
Language: English (Regional Setting: English)
System Manufacturer: Dell Inc.
System Model: Inspiron 3650
BIOS: BIOS Date: 12/07/17 21:58:28 Ver: 05.0000B
Processor: Intel(R) Core(TM) i7-6700 CPU @ 3.40GHz (8 CPUs), ~3.4GHz
Memory: 16384MB RAM
Available OS Memory: 16328MB RAM
Page File: 7285MB used, 25367MB available
Windows Dir: C:\Windows
DirectX Version: DirectX 11
DX Setup Parameters: Not found
User DPI Setting: 120 DPI (125 percent)
System DPI Setting: 96 DPI (100 percent)
DWM DPI Scaling: Disabled
DxDiag Version: 6.01.7601.17514 64bit Unicode
(Full Report Attached)Java 8 Update 171 (64-bit), 04/19/2010
Java 8.0.1710.11The game, however, is set to "Use Java Bundled Runtime."
The JVM Argument line says: -Xmx2G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
Attachments3
duplicates
This seems to be a duplicate of
MC-129383.Thank you. I searched, but didn't see that one. I see that that issue is still OPEN, and hope it gets resolved soon!