Mint-Y GTK2 theme contains invalid GTK2 syntax ("direction") causing GTK2 apps (Steam) to crash

[xannatos]

Description:
On Linux Mint 22.3 Cinnamon, Steam crashes immediately when started from the menu.
The Steam process keeps running, but the UI window disappears.

This is caused by invalid GTK2 syntax in the Mint-Y GTK2 theme.
Steam still uses GTK2 for parts of its UI and fails hard on GTK2 RC parse errors.

Steps to Reproduction:

1. Install Linux Mint 22.3 Cinnamon
2. Use default Mint-Y theme
3. Start Steam from the application menu
4. Steam UI crashes immediately

Expected behavior:
Steam UI should start normally.
GTK2 themes should not contain invalid GTK2 syntax.

Actual behavior:
Steam UI crashes.
Steam process keeps running in background.

Relevant log output:
/usr/share/themes/Mint-Y/gtk-2.0/main.rc:1053:
error: unexpected identifier 'direction', expected character '}'

Workaround:
Starting Steam with:
GTK2_RC_FILES= GTK_THEME=Adwaita steam

or removing Mint-Y GTK2 theme fixes the issue.

Systeminformation:
Linux Mint 22.3 Cinnamon
GTK2 application affected: Steam
Desktop: Cinnamon

Since I'm a Linux beginner, I solved the problem using a chatbot. Therefore, the content of this bug report also comes from the chatbot. Apologies if it's completely nonsensical.

[fredcw]

Steam on manjaro seems to be working ok with Mint-Y.

error: unexpected identifier 'direction', expected character '}'

That's been in Mint-Y gtk-2.0/main.rc unchanged for at least 9 years. It's seems unlikely that is invalid syntax.