diff --git a/.gitignore b/.gitignore
index 5604d9d..23228f7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,3 +9,4 @@
 /firefox-78.9.0esr.source.tar.xz
 /firefox-78.10.0esr.source.tar.xz
 /firefox-78.11.0esr.source.tar.xz
+/firefox-78.12.0esr.source.tar.xz
diff --git a/mozjs78.spec b/mozjs78.spec
index 4f4e06b..f946a84 100644
--- a/mozjs78.spec
+++ b/mozjs78.spec
@@ -23,7 +23,7 @@
 %endif
 
 Name:           mozjs%{major}
-Version:        78.11.0
+Version:        78.12.0
 Release:        1%{?dist}
 Summary:        SpiderMonkey JavaScript library
 
@@ -272,6 +272,9 @@ PYTHONPATH=tests/lib %{__python3} jit-test/jit_test.py -s -t 1800 --no-progress
 %{_includedir}/mozjs-%{major}/
 
 %changelog
+* Tue Jul 13 2021 Frantisek Zatloukal <fzatlouk@redhat.com> - 78.12.0-1
+- Update to 78.12.0
+
 * Wed Jun 02 2021 Frantisek Zatloukal <fzatlouk@redhat.com> - 78.11.0-1
 - Update to 78.11.0
 
diff --git a/sources b/sources
index 3bc8627..eba6267 100644
--- a/sources
+++ b/sources
@@ -1 +1 @@
-SHA512 (firefox-78.11.0esr.source.tar.xz) = d02fc2eda587155b1c54ca12a6c5cde220a29f41f154f1c9b71ae8f966d8cc9439201a5b241e03fc0795b74e2479f7aa5d6b69f70b7639432e5382f321f7a6f4
+SHA512 (firefox-78.12.0esr.source.tar.xz) = 646eb803e0d0e541773e3111708c7eaa85e784e4bae6e4a77dcecdc617ee29e2e349c9ef16ae7e663311734dd7491aebd904359124dda62672dbc18bfb608f0a