Research / Constructs / Code
Inline code and fenced code blocks in five publishing editors
One Markdown fixture, five real publishing editors, tested 2026-08-24. For code the observed result was degraded in X and LinkedIn; kept in WordPress, Substack, and Beehiiv. Every row below is a rule with its own page and its own dated record.
Matches inline_code, code, code_long_line. Fixture markdown-portability-test-v1. Tested 2026-08-24. How these tests are run.
What happens, per destination
| Destination | What happens | Result | Severity | Rule | Confidence | Last tested |
|---|---|---|---|---|---|---|
| X | Code loses its formatting and gets a Code: label. | Degraded | Review | X-CODE-01 | Verified | 2026-08-24 |
| Code loses its formatting and gets a Code: label. | Degraded | Review | LI-CODE-01 | Verified | 2026-08-24 | |
| WordPress | Code is preserved, but a long unbroken line may overflow. | Kept | Review | WP-CODE-01 | Verified | 2026-08-24 |
| WordPress | Inline formatting is preserved. | Kept | Info | WP-EMPH-01 | Verified | 2026-08-24 |
| Substack | Code survives, but a long unbroken line needs a mobile check. | Kept | Review | SUB-CODE-01 | Verified | 2026-08-24 |
| Substack | Inline formatting survives rich paste. | Kept | Info | SUB-EMPH-01 | Verified | 2026-08-24 |
| Beehiiv | Code is kept, but a long unbroken line may overflow in email. | Kept | Review | BEE-CODE-01 | Verified | 2026-08-24 |
| Beehiiv | Inline formatting is kept as Markdown. | Kept | Info | BEE-EMPH-01 | Verified | 2026-08-24 |
Manual steps this creates
- X: Summarize long code or link to it instead. (There is no code control in the composer and backticks stay literal.)
- LinkedIn: Shorten long code or attach it as a document. (Backticks stayed literal and there is no code control.)
- WordPress: Check the post on a narrow screen. (Theme CSS controls overflow; tested long lines exceeded a 390-pixel viewport.)
- Substack: Check the mobile preview. (Code blocks survived; long-line overflow still needs destination review.)
- Beehiiv: Check the email preview before sending. (Fenced code converted natively; long lines needed review in the tested narrow and email previews.)
Limits of what was tested
- Each result describes the surface named beside it, on the date named beside it, and nothing wider.
- A result marked unknown means no dated test covers it. It is not a prediction.
- Rendering is not the same across platform versions, themes, plugins, or email clients.
Prepare a draft
- Check your own draft against all five destinations
- Markdown to WordPress, handoff mode: gutenberg paste
- Markdown to Substack, handoff mode: rich html clipboard
- Markdown to Beehiiv, handoff mode: clean markdown paste
- Markdown to X, handoff mode: plain text
- Markdown to LinkedIn, handoff mode: plain text
Related
- The 8 rules behind this page:
BEE-CODE-01,BEE-EMPH-01,LI-CODE-01,SUB-CODE-01,SUB-EMPH-01,WP-CODE-01,WP-EMPH-01,X-CODE-01 - Every construct, side by side
- The full five-destination matrix