diff --git a/translations-desktop/Dockerfile b/translations-desktop/Dockerfile
index b098438b..28b711d6 100644
--- a/translations-desktop/Dockerfile
+++ b/translations-desktop/Dockerfile
@@ -1,4 +1,4 @@
-FROM ubuntu:22.04
+FROM ubuntu:24.04
 
 MAINTAINER Morris Jobke <hey@morrisjobke.de>
 
@@ -12,7 +12,6 @@ RUN apt-get update -q && \
         curl \
         openssh-client \
         ca-certificates \
-        qttools5-dev-tools \
         qt6-tools-dev-tools \
     && apt-get clean
 
@@ -22,7 +21,7 @@ RUN update-ca-certificates
 RUN cd /root
 RUN curl -o- https://raw.githubusercontent.com/transifex/cli/master/install.sh | bash
 
-ENV PATH=${PATH}:/
+ENV PATH=${PATH}:/usr/lib/qt6/bin:/
 
 RUN mkdir -p /app
 
diff --git a/translations-desktop/handleDesktopTranslations.sh b/translations-desktop/handleDesktopTranslations.sh
index ec3dac68..020aa838 100755
--- a/translations-desktop/handleDesktopTranslations.sh
+++ b/translations-desktop/handleDesktopTranslations.sh
@@ -55,17 +55,23 @@ do
     crashreporter=""
   fi
 
-  lupdate src/gui/ src/cmd/ src/common/ $crashreporter src/csync/ src/libsync/ $resources -ts /branches/$version.ts
+  # copy existing translation file from the branch, this allows `lupdate` to e.g. keep existing plural forms
+  cp "translations/client_en.ts" "/branches/$version.ts"
+
+  lupdate -no-obsolete src/gui/ src/cmd/ src/common/ $crashreporter src/csync/ src/libsync/ $resources -ts /branches/$version.ts
 done
 
 # Merge source translation files and filter duplicates
+# This will be used as the source file for Transifex, it contains all translatable strings from each branch
 lconvert -i /branches/*.ts -o /merged_en.ts
 
-# Fix missing <numerusform> elements (always two are required but lconvert strips out one)
-# Fix paths, changed by lconvert
-sed -e 's/<numerusform><\/numerusform>/<numerusform><\/numerusform><numerusform><\/numerusform>/' -e 's/app\/desktop\/src/src/' /merged_en.ts > translations/client_en.ts
+# Fix paths, changed by lupdate/lconvert.  Needs to be done for all branch-specific translations and the combined one
+for ts_file in /merged_en.ts /branches/*.ts; do
+  sed -i -e 's,app/desktop/src,src,' "$ts_file"
+done
 
-# push sources
+# Copy merged translation to the repo to let `tx` use it as a source file, and push it to Transifex.
+cp /merged_en.ts translations/client_en.ts
 tx push -s
 
 # undo local changes
@@ -91,6 +97,9 @@ do
   mv translations/client_de_DE.ts translations/client_de.ts
   rm -rf nextcloud.client-desktop/de_translation.desktop
   mv nextcloud.client-desktop/de_DE_translation.desktop nextcloud.client-desktop/de_translation.desktop
+  if [ -f "/branches/$version.ts" ]; then
+    cp "/branches/$version.ts" translations/client_en.ts
+  fi
 
   # create git commit and push it
   git add .