Title: Big Picture virtual keyboard treats letters as navigation and repeatedly steals focus (cannot type)

System Information

• OS: Linux Mint 22.3 (Ubuntu 24.04 base)
• Desktop: Cinnamon
• Kernel: 6.17.x
• GPU: NVIDIA (proprietary driver)
• Input device: Manba / Zhixu Xbox-compatible controller
• Steam UI: New Big Picture / Gamepad UI

Problem Summary

When the Big Picture on-screen keyboard is opened, certain letters (notably Q, R, T, O and occasionally numbers) act as UI navigation keys instead of text input.

Side note: During troubleshooting (after changing various Steam controller and overlay settings), an additional behavior appeared:

• Typing works briefly (~0.5 seconds)
• A Big Picture navigation sound (“whoosh”) plays
• Focus is pulled away from the text field
• Typing stops entirely

Restoring Steam’s controller-related settings returned behavior to the original baseline issue (letters acting as navigation).

This affects both:
• physical keyboard
• Steam virtual keyboard

Result: text entry in Big Picture or overlay text fields becomes unreliable or impossible.

Expected Behavior

Keys pressed on either physical or virtual keyboard should insert characters when a text field is active and should not trigger UI navigation or cancel actions.

Actual Behavior

Steam appears to interpret some keyboard input as UI navigation while a text field is active, causing:

• Letters to move selection instead of typing
• Intermittent or lost text focus
• Inability to type reliably in Big Picture or overlay prompts

Reproduction Steps

1. Launch Steam Big Picture
2. Connect Xbox-compatible controller (Manba/Zhixu clone)
3. Open any text field (chat, search, login, rename, etc.)
4. Open Steam on-screen keyboard OR use physical keyboard
5. Type normally

Observed:

• Some letters move UI selection
• Text entry behaves incorrectly or stops working

Troubleshooting Performed

Controller / Input

• Reset Desktop Layout
• Reset Guide Button Chord Layout
• Removed “Show Keyboard” bindings
• Disabled Guide Button focus
• Disabled Steam Input globally
• Enabled Steam Input globally
• Tested for phantom controller inputs (none detected)

Steam Settings

• Disabled Big Picture overlay usage
• Disabled Steam overlay
• Restored controller settings to defaults
• Restarted Steam multiple times

Launch flags / environment

• STEAM_DISABLE_TEXT_INPUT=1
• STEAM_USE_OLD_BIGPICTURE=1
• -oldbigpicture
• -vgui
• Various Big Picture launch combinations
• Per-game launch options

Configuration reset

• Deleted controller_configs
• Deleted steaminput.vdf
• Deleted config.vdf
• Deleted localconfig.vdf
• Restarted client

Temporary change in behavior occurred after altering settings, but restoring defaults returned to the baseline issue.

Additional Notes

The behavior resembles a UI navigation layer activating during text entry, causing keyboard input to be interpreted as controller navigation. The issue occurs with both the virtual keyboard and a physical keyboard.

Frequency

100% reproducible on this system.