diff --git a/build.sh b/build.sh
index 3cb4ff6..17316e4 100755
--- a/build.sh
+++ b/build.sh
@@ -1,15 +1,12 @@
 #!/bin/bash
 
-# update submodule to latest release
-git submodule update --init --recursive
-
-# get latest mastodon release number (needed to tag docker image)
-mastodon_version=`curl -sL https://api.github.com/repos/mastodon/mastodon/releases/latest | jq -r ".tag_name"`
-
 # Change to the main repo
 cd mastodon
 
-export MASTODON_VERSION_FOR_BIRD_UI="main"
+# update submodule to latest main release
+git checkout version/v4.3.0-alpha.1 && git fetch
+
+export MASTODON_VERSION_FOR_BIRD_UI="nightly"
 
 # Create a new folder for the theme
 mkdir -p app/javascript/styles/mastodon-bird-ui
@@ -50,10 +47,10 @@ for i in `ls ../diffs/` ; do patch -N config/locales/"${i/diff/yml}" < ../diffs/
 # If the main branch of the repo build tagged version and latest image
 cd ../
 BRANCH="$(git rev-parse --abbrev-ref HEAD)"
-if [[ "$BRANCH" == "main" ]]; then
-  echo 'Main branch';
+if [[ "$BRANCH" == "nightly" ]]; then
+  echo 'Nightly branch';
   # Build the images for multiple architectures
   cd mastodon
-  docker buildx build --platform linux/amd64,linux/arm64 --push --tag richarvey/mastodon-bird-ui:$mastodon_version --tag richarvey/mastodon-bird-ui:latest . ;
+  docker buildx build --platform linux/amd64,linux/arm64 --push --tag richarvey/mastodon-bird-ui:nightly . ;
 fi
 
diff --git a/mastodon b/mastodon
index c93aaca..b1fbb45 160000
--- a/mastodon
+++ b/mastodon
@@ -1 +1 @@
-Subproject commit c93aacafdea188cac791b62a32e3117a7dc3e9cc
+Subproject commit b1fbb459941822517421b6e4f625f8fd3b2dbde4