Compat hack for 5.3- use_texture_alpha.

mods/nc_api/compat_nodealpha.lua

@@ -0,0 +1,14 @@
+-- LUALOCALS < ---------------------------------------------------------
+local minetest, type
+    = minetest, type
+-- LUALOCALS > ---------------------------------------------------------
+
+if minetest.features.use_texture_alpha_string_modes then return end
+
+local oldreg = minetest.register_item
+function minetest.register_item(name, def, ...)
+	if def and type(def.use_texture_alpha) == "string" then
+		def.use_texture_alpha = def.use_texture_alpha == "blend" or nil
+	end
+	return oldreg(name, def, ...)
+end

mods/nc_api/init.lua

@@ -84,6 +84,7 @@ end
 include("compat_clientversion")
 include("compat_issue10127")
 include("compat_legacyent")
+include("compat_nodealpha")
 
 include("util_misc")
 include("util_hookmeta")