Export filenames

Every export action in Mark It Down stamps its output filename with a short unique id, so re-exporting the same document never overwrites a prior file and you can copy-paste the suffix to refer back to a specific run.

Format

<basename>--<id>.<ext>

• <basename> — derived from the source file's name (or a fixed label like code, diagram, table for non-document exports). Sanitized to [A-Za-z0-9._-], falling back to export if empty.
• <id> — first 8 hex characters of crypto.randomUUID() (~32 bits of entropy, ~4 billion values).
• <ext> — the export format: md, txt, html, pdf, png, docx, csv, json, xlsx, svg.

Examples

Action	Filename
Export PDF on roadmap.md	roadmap--3a7f0c19.pdf
Export PNG on roadmap.md	roadmap--c4e6810b.png
Export DOCX on roadmap.md	roadmap--98a142f7.docx
Code-block PNG export	code--71ed4f02.png
Mermaid SVG export	diagram--0bf81d77.svg
Mermaid PNG export	diagram--be20a1c5.png
Table → CSV	table--5dd9a206.csv
Table → Excel (xlsx)	table--5dd9a206.xlsx
Table → JSON	table--5dd9a206.json

What this does NOT affect

• Save / Save As keep using the source filename (or untitled.md for a brand-new doc) — they're authoring actions, not exports, so the user picks the final name.
• The system Save dialog still appears for every export and the user can override the suggested name before writing.

Implementation

Helpers live in apps/electron/renderer/renderer.ts:

defaultExportName(ext) (the helper used by every exportAs(format) branch) is now a thin wrapper around uniqueExportName so PDF, PNG, DOCX, HTML, MD, TXT all flow through the same path. Code-block, mermaid, and table exports call uniqueExportName directly.