diff --git a/process-official-tarball b/process-official-tarball
index c3f4077..9b6e82c 100755
--- a/process-official-tarball
+++ b/process-official-tarball
@@ -22,6 +22,8 @@ rm -vr ./process-tarball-dir/*/comm/third_party/rust/wast/tests/parse-fail/confu
 
 # We uses system freetype2
 rm -vrf ./process-tarball-dir/*/modules/freetype2
+# We use system zlib
+rm -vrf ./process-tarball-dir/*/modules/zlib
 
 processed_tarball=${1/source/processed-source}
 
diff --git a/thunderbird.spec b/thunderbird.spec
index 0d5edee..d117367 100644
--- a/thunderbird.spec
+++ b/thunderbird.spec
@@ -476,7 +476,6 @@ Provides: bundled(xsimd)
 Provides: bundled(xsimd)
 Provides: bundled(xz-embedded)
 Provides: bundled(ycbcr)
-Provides: bundled(zlib)
 Provides: bundled(zstd)
 Provides: bundled(Zycore)
 Provides: bundled(Zydis)