diff --git a/Dockerfile b/Dockerfile
index 4e0518a..fcfa7d3 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -19,7 +19,7 @@ FROM jlesage/baseimage-gui:alpine-3.12-v3.5.6
 ARG DOCKER_IMAGE_VERSION=unknown
 
 # Define software versions.
-ARG FIREFOX_VERSION=79.0-r0
+ARG FIREFOX_VERSION=81.0-r0
 ARG JSONLZ4_VERSION=c4305b8
 ARG LZ4_VERSION=1.8.1.2
 #ARG PROFILE_CLEANER_VERSION=2.36