Blender: 2.81 since https://developer.blender.org/rB26911ba1e26b90d7fafcd2e877a52c55181896c1
This commit introduced a new SOCK_COMPACT flag.
This breaks the Normal node and possibly other nodes that have a vector with a PROP_DIRECTION subtype.
Simple fix is to just add the SOCK_COMPACT to the socket template but a proper fix should add a working unit vector widget button.
diff --git a/source/blender/nodes/shader/nodes/node_shader_normal.c b/source/blender/nodes/shader/nodes/node_shader_normal.c
index 074cc3dd87f..c6eaccaf7dd 100644
--- a/source/blender/nodes/shader/nodes/node_shader_normal.c
+++ b/source/blender/nodes/shader/nodes/node_shader_normal.c
@@ -25,7 +25,7 @@
/* **************** NORMAL ******************** */
static bNodeSocketTemplate sh_node_normal_in[] = {
- {SOCK_VECTOR, 1, N_("Normal"), 0.0f, 0.0f, 0.0f, 1.0f, -1.0f, 1.0f, PROP_DIRECTION},
+ {SOCK_VECTOR, 1, N_("Normal"), 0.0f, 0.0f, 0.0f, 1.0f, -1.0f, 1.0f, PROP_DIRECTION, SOCK_COMPACT},
{-1, 0, ""},
};