diff --git a/apt/sources.list.d/steam-beta.list b/apt/sources.list.d/steam-beta.list
new file mode 100644
index 0000000..4d6c4d0
--- /dev/null
+++ b/apt/sources.list.d/steam-beta.list
@@ -0,0 +1,3 @@
+# Uncomment these lines to try the beta version of the Steam launcher
+#deb [arch=amd64,i386 signed-by=/usr/share/keyrings/steam.gpg] https://repo.steampowered.com/steam/ beta steam
+#deb-src [arch=amd64,i386 signed-by=/usr/share/keyrings/steam.gpg] https://repo.steampowered.com/steam/ beta steam
diff --git a/apt/sources.list.d/steam-stable.list b/apt/sources.list.d/steam-stable.list
new file mode 100644
index 0000000..028764e
--- /dev/null
+++ b/apt/sources.list.d/steam-stable.list
@@ -0,0 +1,2 @@
+deb [arch=amd64,i386 signed-by=/usr/share/keyrings/steam.gpg] https://repo.steampowered.com/steam/ stable steam
+deb-src [arch=amd64,i386 signed-by=/usr/share/keyrings/steam.gpg] https://repo.steampowered.com/steam/ stable steam
diff --git a/profile.d/flatpak.sh b/profile.d/flatpak.sh
index 395f93b..4b88baf 100644
--- a/profile.d/flatpak.sh
+++ b/profile.d/flatpak.sh
@@ -1,3 +1,4 @@
+# shellcheck shell=sh
 if command -v flatpak > /dev/null; then
     # set XDG_DATA_DIRS to include Flatpak installations