Steam Deck OLED Game Mode Touchscreen Multi-Touch Failure

Start by comparing touchscreen event handling in Game Mode and Desktop Mode, focusing on Steam Input, Gamescope, and the touchscreen event path named in the report. Reproduce on a Steam Deck OLED with two simultaneous touches, then check whether a single touch works again after returning from the Steam menu. Done means multi-touch no longer leaves subsequent single-touch input unresponsive.

Bug Report: Steam Deck OLED Game Mode Touchscreen Becomes Unresponsive After Multi-Touch Input

Device: Steam Deck OLED
Operating System: Latest SteamOS Stable
Date: November 6, 2026

Issue Description

The touchscreen behaves differently between Game Mode and Desktop Mode.

In Desktop Mode, multi-touch works normally. However, in Game Mode, the following issue occurs:

1. Single-finger touchscreen input works normally.
2. When two fingers touch the screen simultaneously, the second touch cannot be registered correctly.
3. After simultaneous two-finger input, even single-finger touchscreen input stops responding.
4. Pressing the Steam button and returning to the game restores single-finger touchscreen functionality.

Reproduction Steps

1. Boot Steam Deck OLED into SteamOS Game Mode.
2. Launch a game that supports touchscreen input.
3. Tap the screen with one finger. It works normally.
4. Touch two different screen positions simultaneously using two fingers.
5. Release both fingers and try tapping with one finger again.
6. Observe that touchscreen input is no longer working correctly.
7. Press the Steam button, return to the game, and test again.

Expected Behavior

Touchscreen input should remain responsive after simultaneous touch events. At minimum, a multi-touch interaction should not cause subsequent single-touch input to become unresponsive.

Actual Behavior

Multi-touch input causes touchscreen interaction to stop responding correctly in Game Mode. Pressing the Steam button and returning to the game restores single-touch functionality.

Additional Information

• The issue occurs on two separate, unmodified Steam Deck OLED devices.
• Both devices are running the latest SteamOS Stable release.
• Desktop Mode supports simultaneous multi-touch normally.
• The issue occurs across multiple touchscreen-compatible games, not just one specific game.
• Both devices reproduce the same behavior.

Please investigate whether this is related to Steam Input, Gamescope, or touchscreen event handling in Game Mode.