Theme detection fails to use dark variant despite OSC 11 returning dark background color

[owod24]

Description

The catppuccin theme (and other themes with light/dark variants) always shows the light variant, even though OSC 11 queries return a dark background color from the terminal. This began happening today with no known configuration changes.
This appears to be related to issues #19254 and #20926.

Expected behavior:
Themes with dark/light variants should respect the terminal's dark background and display the dark variant based on OSC 11 response.
Actual behavior:
Always displays the light variant regardless of OSC 11 response.

Plugins

superpowers

OpenCode version

v1.4.1

Steps to reproduce

1. Open opencode in cmux terminal (configured for dark mode)
2. Select catppuccin theme via /theme command
3. Observe that light variant (Latte) is shown instead of dark variant (Mocha)
   Diagnostic information:

• OSC 11 query response: rgb:1e1e/1e1e/2e2e (dark background - confirmed dark)
• cmux appearance mode: dark (confirmed in preferences)
• Theme detection: works correctly with system theme

Screenshot and/or share link

No response

Operating System

macOS 26.2

Terminal

cmux

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• no longer respects system theme (macos ghostty) #20926: Same symptom — themes with light/dark variants always display the light variant regardless of system/terminal dark mode setting (macOS)
• Auto theme mode does not work in tmux popup #19254: Auto theme mode not working correctly (referenced in your issue)

If your issue is distinct from the above, please add clarifying details explaining how it differs.