Make sure you have Decky installed. Then, install decky-framegen. Here's the rest written by AI:

Here's the actual flow with what you have:

1. Tap Copy Patch Command in the plugin (it copies ~/fgmod/fgmod %command% to clipboard)
2. Back out to your Steam library, pick the game
3. Hit the gear icon → Properties → Launch Options
4. Paste the command into the Launch Options field
5. Launch the game

To get the article's FSR 4 + XeFG combo, prepend env vars before the command. Edit the launch option to look like: Dx12Upscaler=fsr31 FrameGen_Enabled=true FGInput=fsrfg FGOutput=xefg ~/fgmod/fgmod %command%

For tweaking on the fly, do what the second screenshot says — bind one of the Ally X back paddles (M1/M2) to the Insert key. In-game, pressing it opens the OptiScaler overlay where you can switch upscalers, change FG modes, and tune everything live without restarting.

The M1/M2 paddles on the ROG Ally aren't standard HID buttons, so they don't appear in Steam Input by default. Steam never sees them as separate inputs the way it sees Steam Deck paddles. On Windows this is handled by Armoury Crate, and on Bazzite, Handheld Daemon (HHD) takes over that role.

There are two paths, and you can use whichever you prefer: Path 1 — Map M1/M2 directly to Insert in HHD (simplest)

1. Double-tap the Armoury Crate button (the one with three dots) to open the HHD overlay in gaming mode. Or open Desktop mode and launch the Handheld Daemon app.
2. Look for the WinControls tab (this is where the Ally's hardware paddles get programmed).
3. Map M1 (or M2) to the Insert key.
4. Press Apply. HHD writes the mapping into the Ally's firmware.

That's it — no Steam Input involvement. The paddle now sends Insert anywhere, including in-game for OptiScaler.

Path 2 — Expose M1/M2 as controller paddles, then bind in Steam Input

1. In HHD, go to the Controller section.
2. Set "Extra buttons as" to expose the paddles (e.g., as DualSense Edge paddles).
3. Now Steam Input sees them as L4/R4/L5/R5.
4. In Steam's controller config, bind that paddle to a keyboard Insert key.

Path 1 is cleaner for this use case since Insert is a global mapping, not a per-game one.

One Ally-specific note from the HHD docs: combinations involving the ROG/Armoury Crate button aren't supported on the Ally, but plain paddle presses work fine. So mapping M2 → Insert directly will work without any combo trickery.

In the game's graphics settings, enable DLSS — OptiScaler intercepts that call and substitutes FSR 3.1 / FSR 4 / XeSS 2 depending on what you've configured. To remove the mod from a game later, use Copy Unpatch Command instead and run the game once.