Fix a few characters for tmux

[dgageot]

No description provided.

[docker-agent]

Review Summary

Assessment: 🟡 NEEDS ATTENTION

This PR changes the Unicode characters used for the scrollbar track and thumb to fix tmux rendering issues. While the change addresses the stated goal, there is a potential compatibility concern worth considering.

Analysis

The change replaces:

• Track character: │ (U+2502, Box Drawing Light Vertical) → ⎪ (U+23AA, Left Vertical Box Line Extension)
• Thumb character: │ (U+2502, Box Drawing Light Vertical) → ┃ (U+2503, Box Drawings Heavy Vertical)

Finding

One medium-severity concern was identified regarding cross-terminal compatibility of the new Unicode characters.

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Note: This is an automated review. The finding represents a technical tradeoff worth evaluating, not necessarily a blocking issue.

[docker-agent]

⚠️ MEDIUM: Terminal Compatibility Concern

The new Unicode characters may have compatibility issues across different terminal environments:

• Track character ⎪ (U+23AA): This is from the Mathematical Operators block (intended for extending vertical box drawing) rather than the standard Box Drawing block. Some terminals or fonts may:

  • Render it with incorrect width
  • Display it as a missing glyph
  • Calculate character width differently (especially in tmux)

• Previous character │ (U+2502): Part of the standard Box Drawing set with better cross-terminal support

Context: While this change intentionally fixes tmux rendering (per the PR title), it may introduce compatibility issues in other terminal emulators or font configurations. This is a classic engineering tradeoff: fixing a known issue (tmux) while potentially creating unknown issues (other terminals).

Recommendation: Consider testing this change across multiple terminal emulators (iTerm2, Terminal.app, Windows Terminal, Alacritty, etc.) to ensure the new characters render correctly in common environments.