Math Delimiter Trigger Roadmap Slice

Goal

Promote math delimiter triggers into the active editor-behavior roadmap as one explicit queued item instead of leaving them stranded as a parity-only backlog bullet.

Scope

This slice covers the markdown-sensitive math input-trigger family:

• $ selection-wrap over an existing selection
• $ pair-on-type at an empty insertion point
• $$ block trigger / block detection
• boundary decision for $$ plus Enter promotion

This is not a general math rendering or equation-feature lane.

Why It Deserves A Real Roadmap Item

• the authority split already exists
• the behavior rows are already decomposed in research and spec guidance
• the work crosses more than one local seam:
  • math package
  • neighboring key/input behavior
  • editor-behavior law and protocol truth

That is too real to leave as an unnamed follow-up bullet.

Inputs

• master-roadmap.md
• markdown-parity-matrix.md
• math-delimiter-trigger-audits-must-split-selection-wrap-pair-on-type-and-block-detection.md
• 2026-04-10-autoformat-runtime-alignment-and-extension-plan.md

Proposed Queue Position

Put this immediately after Toggle Rewrite and before the broader date/media expansion lanes.

Why:

• still a markdown-feature item
• narrower and more grounded than date/media expansion
• already has a clearer authority split than the wider date/media follow-up

Exit

• the roadmap names math delimiter triggers explicitly
• the roadmap states that package/input ownership is row-split, not one fake global math-trigger winner
• parity stops being the only place that names the work

Progress

• [done] Added the supporting roadmap slice doc.
• [done] Added the full implementation plan: 2026-04-10-math-delimiter-trigger-implementation-plan.md
• [done] Promoted math delimiter triggers into the canonical roadmap.
• [done] Promoted the same item into the active mirror implementation roadmap.
• [done] Updated parity wording so math triggers are no longer only a parity backlog bullet.