Infovarious Classic to Block Converter

Infovarious Classic to Block Converter converts posts written in the classic editor (posts that contain no blocks) into block-editor content, in bulk, with safety checks.

It was built for a large Japanese blog with a custom theme, many shortcodes and affiliate links, where “convert and hope” was not acceptable.

How it keeps your site safe

• Output comparison: for every post, the plugin simulates how the front end renders the content before and after conversion. If they differ, the post is not split into blocks; it is kept as a single Classic block, or skipped if even that would change the output.
• Link and shortcode check: links, images, scripts, shortcodes and embed URLs must be identical before and after, otherwise the post is not split.
• Read-only dry run, status and preview: these never write to the database. Only “Run conversion” and “Roll back / delete backups” write.
• Per-post backup: the original content is saved in post meta (_ctbc_original_content) and read back before the post is updated. Rolling back restores it, unless you edited the post after conversion.
• Conflict-safe update: a post edited while the batch runs is skipped.
• Modified date is kept, and save hooks of other plugins are not triggered.
• Pages are excluded. Already-block posts are skipped; posts that mix blocks with old classic parts are reported for review.
• Conversion history (title, URL, mode, time) and a real-site preview for administrators.

Content that cannot be expressed safely as a core block (for example affiliate HTML, theme-specific shortcodes) is kept verbatim in Custom HTML or Shortcode blocks.

Tested with a Japanese site using the AFFINGER7 theme (with a child theme and its shortcodes) and Pochipp blocks. It is not affiliated with or endorsed by the theme’s author. Results on other themes and plugins can differ, so always run the dry run and preview first.

The admin UI is in Japanese. Translation is not yet included.