🐛 Fix terminal rendering issues on iOS Safari via DOM renderer

[owine]

What

Add --client-option rendererType=dom to the ttyd options in the run script.

Why

xterm.js defaults to WebGL → Canvas → DOM renderer order. On iOS Safari, the WebGL and Canvas renderers produce garbled, unreadable terminal output. Pinning to the DOM renderer fixes this.

This is a separate issue from the theme color change in #1033/#1034. That PR addressed unreadable text contrast; this addresses the renderer producing garbled output on iOS.

Closes #1016
Closes #1026
Closes #1027

Summary by CodeRabbit

• Chores
  • Switched the web terminal client to DOM-based rendering. This may change visual appearance, text/emoji rendering, and performance characteristics in the in-browser terminal display.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 21a09b22-1a1c-4783-91c5-4b22b9152a4d

📥 Commits

Reviewing files that changed from the base of the PR and between 147859f and 929555a.

📒 Files selected for processing (1)

• ssh/rootfs/etc/s6-overlay/s6-rc.d/ttyd/run

✅ Files skipped from review due to trivial changes (1)

• ssh/rootfs/etc/s6-overlay/s6-rc.d/ttyd/run

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Walkthrough

Added a ttyd startup option to force xterm.js to use DOM rendering by appending --client-option rendererType=dom to the ttyd options array in the s6 service run script.

Changes

Cohort / File(s)	Summary
ttyd service configuration ssh/rootfs/etc/s6-overlay/s6-rc.d/ttyd/run	Appended --client-option rendererType=dom to the ttyd command options to set xterm.js renderer type to dom; no other command construction or control flow changes.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

Possibly related PRs

• Revert "🐛 Fix unreadable terminal text in Safari/iOS and Firefox" #1034 — Modifies the same ttyd startup script's command-line options (related changes to client/theme flags).

Poem

🐰 I hopped into run, tweaked one small line,
Told ttyd’s xterm.js to draw with DOM fine.
No canvas blur, just clearer text in view,
A tiny change — a rabbit’s joy for you. 🥕

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title mentions fixing terminal rendering issues on iOS Safari via DOM renderer, which aligns with the change of adding DOM renderer option to ttyd configuration.
Linked Issues check	✅ Passed	The code change forces DOM renderer for xterm.js, which directly addresses the rendering corruption reported in iOS/iPad Safari (issues #1026, #1027) and Firefox color issues (#1016).
Out of Scope Changes check	✅ Passed	The PR only modifies the ttyd startup command to add a single client option flag, which is directly scoped to fixing the rendering issues identified in linked issues.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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