diff --git a/umu/umu_consts.py b/umu/umu_consts.py
index 59a20aecc..cea5534cf 100644
--- a/umu/umu_consts.py
+++ b/umu/umu_consts.py
@@ -16,30 +16,35 @@
     "getnativepath",
 }
 
-# Installation path of the runtime files
-# Flatpak will be detected as outlined by systemd
-# See https://systemd.io/CONTAINER_INTERFACE
-UMU_LOCAL: Path = (
-    Path.home().joinpath(
-        ".var", "app", "org.openwinecomponents.umu.umu-launcher", "data", "umu"
+XDG_DATA_HOME: Path = (
+    Path(os.environ["HOST_XDG_DATA_HOME"])
+    if os.environ.get("HOST_XDG_DATA_HOME")
+    else (
+        Path(os.environ["XDG_DATA_HOME"])
+        if os.environ.get("XDG_DATA_HOME")
+        else Path.home().joinpath(".local", "share")
     )
-    if os.environ.get("container") == "flatpak"  # noqa: SIM112
-    else Path.home().joinpath(".local", "share", "umu")
 )
 
-# Temporary directory for downloaded resources moved from tmpfs
-UMU_CACHE: Path = (
-    Path.home().joinpath(
-        ".var",
-        "app",
-        "org.openwinecomponents.umu.umu-launcher",
-        "cache",
-        "umu",
-    )
-    if os.environ.get("container") == "flatpak"  # noqa: SIM112
-    else Path.home().joinpath(".cache", "umu")
+XDG_CACHE_HOME: Path = (
+    Path(os.environ["XDG_CACHE_HOME"])
+    if os.environ.get("XDG_CACHE_HOME")
+    else Path.home().joinpath(".cache")
 )
 
+# Installation path of the runtime files that respects the XDG Base Directory
+# Specification and Systemd container interface.
+# See https://systemd.io/CONTAINER_INTERFACE
+# See https://specifications.freedesktop.org/basedir-spec/latest/index.html#basics
+# NOTE: For Flatpaks, the runtime will be installed in $HOST_XDG_DATA_HOME
+# then $XDG_DATA_HOME as fallback, and will be required to update their
+# manifests by adding the permission 'xdg-data/umu:create'.
+# See https://github.com/Open-Wine-Components/umu-launcher/pull/229#discussion_r1799289068
+UMU_LOCAL: Path = XDG_DATA_HOME.joinpath("umu")
+
+# Temporary directory for downloaded resources moved from tmpfs
+UMU_CACHE: Path = XDG_CACHE_HOME.joinpath("umu")
+
 # Constant defined in prctl.h
 # See prctl(2) for more details
 PR_SET_CHILD_SUBREAPER = 36