Felix Wagner

Can confirm. Looking at a map while standing in the mapped area crashes the client. Here's a typical error log I get:

[18:30:37] [Server thread/WARN]: Failed to handle packet for /...:*
q: Ticking player
at yi.i(SourceFile:475) ~[server.jar:?]
at yz.b(SourceFile:198) ~[server.jar:?]
at lv.a(SourceFile:234) ~[server.jar:?]
at yy.c(SourceFile:171) [server.jar:?]
at net.minecraft.server.MinecraftServer.b(SourceFile:872) [server.jar:?]
at xh.b(SourceFile:345) [server.jar:?]
at net.minecraft.server.MinecraftServer.a(SourceFile:799) [server.jar:?]
at net.minecraft.server.MinecraftServer.run(SourceFile:658) [server.jar:?]
at java.lang.Thread.run(Thread.java:834) [?:?]
Caused by: java.lang.IllegalArgumentException: Cannot get property cdt{name=axis, clazz=class fr$a, values=[x, y, z]} as it does not exist in Block{minecraft:dark_oak_wall_sign}
at cct.c(SourceFile:93) ~[server.jar:?]
at btc.a(SourceFile:58) ~[server.jar:?]
at ccu$a.d(SourceFile:691) ~[server.jar:?]
at bib.a(SourceFile:171) ~[server.jar:?]
at bib.a(SourceFile:364) ~[server.jar:?]
at bhw.a(SourceFile:452) ~[server.jar:?]
at bbp.j(SourceFile:290) ~[server.jar:?]
at bbq.l(SourceFile:575) ~[server.jar:?]
at amy.h(SourceFile:2175) ~[server.jar:?]
at bbq.h(SourceFile:274) ~[server.jar:?]
at yi.i(SourceFile:411) ~[server.jar:?]
... 8 more

If you're affected, spam-press any number button that is not the map you're holding while joining, you have a small window in which you can switch items.