Opusplan[1m] and Clear screen patches fail to find their patterns on Claude Code 2.1.227 (tweakcc 4.3.2)

[rpickmans]

Environment

• tweakcc 4.3.2 (npm, npx tweakcc@4.3.2 --apply --yes)
• Claude Code 2.1.227 (@anthropic-ai/claude-code via npm, native binary, macOS arm64 / Darwin 25.6)

Both patches applied cleanly on CC 2.1.226 with this same tweakcc 4.3.2. They broke after upgrading to CC 2.1.227 (released 2026-08-10).

Failing patches + verbatim errors

Opusplan[1m] support:

patch: opusplan1m: patchModelSelectorOptions: failed to find model selector pattern
patch: opusplan1m: failed to apply model selector options patch

Clear screen command:

patch: findSlashCommandListEndPosition: failed to find arrayStartPattern
patch: writeSlashCommandDefinition: failed to find slash command array end position

Likely cause (correlating with the CC 2.1.227 changelog)

• "Improved slash-command menu: blue now marks only the selected row, matched characters are bolded instead of recolored, and emoji or accented names keep their glyphs" — plausibly restructured the slash-command array that findSlashCommandListEndPosition anchors to.
• "Fixed feature flags being evaluated without the user's subscription tier when a session started with an expired login token" — a change in model-gating/selection logic, near where patchModelSelectorOptions matches.

Notes

• Long-standing pattern misses on my setup (toolsets: computeToolsFilter, mcpStartup: MCP_SERVER_CONNECTION_BATCH_SIZE, agentsMd: fs expression) predate 2.1.227 and are not part of this report.
• All other patches, including all system-prompt patches, apply fine on 2.1.227 and the patched binary runs cleanly (claude --version reports both 2.1.227 (Claude Code) and 4.3.2 (tweakcc)).

[rpickmans]

Still failing on Claude Code 2.1.228 (released 2026-08-11), tweakcc 4.3.2, same setup as above (npm native binary, macOS arm64 / Darwin 25.6).

The reason I'm following up: 2.1.228 changed code in both of the regions I speculated about, and neither patch recovered. So this is not a transient anchor shift that the next CC release drifts back — it looks structural.

Errors are character-identical to 2.1.227

patch: opusplan1m: patchModelSelectorOptions: failed to find model selector pattern
patch: opusplan1m: failed to apply model selector options patch
patch: findSlashCommandListEndPosition: failed to find arrayStartPattern
patch: writeSlashCommandDefinition: failed to find slash command array end position

Why 2.1.228 is informative

Relevant 2.1.228 changelog entries:

• "Fixed interactive sessions that could stop redrawing entirely, while the process kept running, after a rare internal layout error" — TUI rendering, near the clear-screen patch site.
• "Fixed /tui reverting the session to an earlier model when /model had been changed since the last response" — model-selection state, near where patchModelSelectorOptions anchors.
• "Updated terminal title busy-spinner glyphs to reduce tab-bar jitter on some terminals" — also TUI.

Both neighbourhoods were touched and both patches still miss. Also worth noting: 2.1.228 has no slash-command-menu entry at all (that was the 2.1.227 "Improved slash-command menu" change I flagged originally), so the clear-screen failure is persisting independently of any further slash-command work rather than tracking ongoing churn in that menu.

Failure set is unchanged between the two releases

Identical on 2.1.227 and 2.1.228: opusplan1m, clear-screen, plus my pre-existing long-standing misses (toolsets: computeToolsFilter, mcpStartup: MCP_SERVER_CONNECTION_BATCH_SIZE, agentsMd: fs expression) and an unconfigured input-chevron-color. Nothing new broke, and nothing recovered.

Everything else still applies cleanly, and the patched binary is healthy — claude --version reports both 2.1.228 (Claude Code) and 4.3.2 (tweakcc), and a headless invocation returns normally.

One incidental data point in case it's useful for #900/#901: on this run tweakcc could not fetch prompt data for 2.1.228 ("Prompts file not found for Claude Code v2.1.228. This version was released within the past day or so") and skipped system-prompt customization entirely — even though the apply ran roughly 24 hours after the 2.1.228 npm publish. On a previous release the prompt data had landed the same day, so that window seems to vary quite a bit.