Fix build for error with grantedEffect on gems

editPathOfBuildingBuild.sh

@@ -19,6 +19,13 @@ sed -E -i '' "$SED_COMMAND" src/Modules/BuildSiteTools.lua
 # Do not remove SSL for LaunchInstall and Update as that's more sensitive, but
 # also unused.
 
+# Add nil checks for grantedEffect. Without it, we got an error on 2023-12-18:
+# "Error loading main script: Data/Uniques/Special/Generated.lua:239 attempt
+# to index local 'grantedEffect' (a nil value)
+# ModParser.lua got a similar error
+sed -i '' 's/if grantedEffect.support/if grantedEffect ~= nil and grantedEffect.support/' src/Data/Uniques/Special/Generated.lua
+sed -i '' 's/if not grantedEffect.hidden/if grantedEffect ~= nil and not grantedEffect.hidden/' src/Modules/ModParser.lua
+
 # Run remaining setup
 unzip runtime-win32.zip lua/xml.lua lua/base64.lua lua/sha1.lua
 mv lua/*.lua .