diff --git a/CHANGELOG.md b/CHANGELOG.md
index fab7ca3f0..811aa694f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # CHANGELOG - sitespeed.io
 
+## UNRELEASED
+### Added
+* Changed to Firefox 76 in the Docker container.
+
 ## 12.8.1 - 2020-05-05
 ### Fixed
 * Reverted to Python 2 in the Docker container to make TSProxy work again.
diff --git a/Dockerfile b/Dockerfile
index 4f6f55544..f173de6c8 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM sitespeedio/webbrowsers:chrome-81.0-firefox-75.0-c
+FROM sitespeedio/webbrowsers:chrome-81.0-firefox-76.0
 
 ENV SITESPEED_IO_BROWSERTIME__XVFB true
 ENV SITESPEED_IO_BROWSERTIME__DOCKER true
diff --git a/Dockerfile-slim b/Dockerfile-slim
index 1ddf27ecc..d5eea27a8 100644
--- a/Dockerfile-slim
+++ b/Dockerfile-slim
@@ -6,7 +6,7 @@ ENV SITESPEED_IO_BROWSERTIME__BROWSER firefox
 ENV SITESPEED_IO_BROWSERTIME__VISUAL_METRICS false
 ENV SITESPEED_IO_BROWSERTIME__HEADLESS true
 
-ENV FIREFOX_VERSION 75.0
+ENV FIREFOX_VERSION 76.0
 
 ENV PATH="/usr/local/bin:${PATH}"