Research / Rules / SUB-IMAGE-01
SUB-IMAGE-01
Remote images are imported and rewritten by Substack. This applies to Substack, where the result is kept.
Affects Substack. Matches image_remote. Fixture markdown-portability-test-v1.
What happens, per destination
| Destination | Tested surface | Result | Severity | Confidence | Last tested |
|---|---|---|---|---|---|
| Substack | Substack web post editor | Kept | Review | Verified | Tested 2026-08-24. |
Why, and what to do
The tested paste showed Substack importing the remote asset onto its own CDN.
No manual step is needed for this rule.
Limits of this rule
- It describes the surface and date in the table above, not every version, theme, or plugin.
- Reading it in isolation hides the other rules that touch the same draft.
- A rule is only as current as the test date beside it.
Related
- All Substack rules, and the Substack test record.
- The full rule set, also available as rules.json.
- Check your own draft against all five