Ignore invalid UTF-8 in config.vdf

Ignore invalid UTF-8 characters when parsing `config.vdf`. These
sometimes appear under `SDL_GamepadBind`, which might be related to the
library. In any case, we do not use any of that data so we can safely
ignore this error.

Fixes #317

CHANGELOG.md

@@ -11,6 +11,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 ### Changed
  - `protontricks -c` and `protontricks-launch` now use the current working directory instead of the game's installation directory. `--cwd-app` can be used to restore old behavior. Scripts can also `$STEAM_APP_PATH` environment variable to determine the game's installation directory; this has been supported (albeit undocumented) since 1.8.0.
 
+### Fixed
+ - Fix Protontricks crash when `config.vdf` contains invalid UTF-8 characters
+
 ## [1.11.1] - 2024-02-20
 ### Fixed
  - Fix Protontricks crash when custom Proton has an invalid or empty `compatibilitytool.vdf` manifest

src/protontricks/steam.py

@@ -655,7 +655,10 @@ def _get_tool_app(compat_tool_name, steam_apps, steam_play_manifest):
     # Multiple configuration values might be found. In such case, select the
     # one with the highest priority.
     config_vdf_path = steam_path / "config" / "config.vdf"
-    content = config_vdf_path.read_text()
+    # config.vdf might contain invalid UTF-8 characters in the
+    # `SDL_GamepadBind` field. We don't use that in any way, so we can deal
+    # with the invalid characters by just ignoring them.
+    content = config_vdf_path.read_text(errors="replace")
 
     vdf_data = lower_dict(vdf.loads(content))