UI: on a desktop keep the desktop's own scale (1.0), not a cap of 1.5

CHANGELOG.md

@@ -12,7 +12,7 @@ one per merged pull request.
 - `645b331` **feat: the GNOME theme installs GNOME Settings with the "GNOME Desktop" panel (dock, desktop icons, tiling) as a prebuilt package, downloaded from the `settings` release of steamify-gnome-theme (built by GitHub Actions on current Arch, rebuilt weekly) and checked against its `.sha256`; a failure keeps the stock Settings. Turning the theme off puts the stock `gnome-control-center` back. Installs with the GNOME theme on re-apply it (feature version 2.13.0)**
 
 - **feat: after the GNOME theme is applied in a GNOME session, the app's done screen has "Restart GNOME" (GNOME Shell on Wayland can't restart in place, and the dock, extensions and Settings panel only show after a new login): with GDM autologin (the SteamOS conversion) Steamify's relogin helper logs the user straight back into the session they were in (without changing the session gaming mode's boot goes back to), else it is a plain logout (`gnome-session-quit`)**
-- **fix: the app on a desktop (a window, however large, also fullscreen) stops scaling at 1.5: on a 1440p or ultrawide monitor it was twice as big as designed (the scale followed the screen's height). The TV mode (`--fullscreen`, gamescope) still scales to the screen**
+- **fix: the app on a desktop (a window, however large, also fullscreen) keeps the desktop's own scale instead of blowing its 1280x720 layout up to the screen's height (twice as big on a 1440p or ultrawide monitor): the layout fills the window at the scale of GNOME or KDE, and only a window smaller than 1280x720 shrinks it. The TV mode (`--fullscreen`, gamescope) still scales to the screen**
 
 ## 2.12.0 - 2026-10-13
 

ui/qml/Main.qml

@@ -36,9 +36,11 @@ ApplicationWindow {
     // own shape, so the bars reach the edges and the content fills it.
     Item {
         id: stage
-        // On a desktop (a window, however large) the scale stops at 1.5: a 1440p or ultrawide monitor would otherwise show
+        // On a desktop (a window, however large) the UI keeps the desktop's own scale: 1 here is one logical pixel, which Qt
-        // everything twice as big. The TV mode (--fullscreen, gamescope) scales to the screen: it is read from the couch.
+        // multiplies by the scale of GNOME or KDE, like any other app (a 1440p or ultrawide monitor would otherwise show
-        readonly property real k: Math.min(win.width / 1280, win.height / 720, win.fullscreen ? Infinity : 1.5)
+        // everything twice as big). Only a window smaller than the layout shrinks it. The TV mode (--fullscreen, gamescope)
+        // scales to the screen: it is read from the couch.
+        readonly property real k: Math.min(win.width / 1280, win.height / 720, win.fullscreen ? Infinity : 1)
         width: win.width / k; height: win.height / k
         transformOrigin: Item.TopLeft
         scale: k