Post Numbers

Adds a #1, #2, #3... number to each post in a discussion. Helpful for referring to specific posts ("see #4 above") and giving readers a sense of where they are in a long thread.

Ported to Flarum 2.0 from ziven/flarum-post-number (MIT).

What it does

Extends CommentPost.headerItems to append a small #N label to each post's header, where N is the post's sequence number within its discussion. Hidden posts are skipped, matching the original extension's behavior.

What it counts

The number comes from Flarum's own per-discussion post number, not a count the extension keeps. That has two consequences worth knowing:

• Numbers are stable. A post keeps its number for the life of the discussion, so #42 in a quoted link still points at the same post later.
• Numbers can have gaps. Deleting a post does not renumber the ones after it. A discussion that has had posts removed will skip numbers, which is correct — renumbering would break every existing deep link.

Hidden posts are skipped entirely: if a post is hidden, no number is rendered for it rather than a number for something you cannot read.

What it does NOT do

• No settings and no migrations.
• It does not renumber, or offer a "count only visible posts" mode — see the gap behaviour above.
• It does not add its own permalink or anchor. Flarum's post menu already has "Permalink", and the number sits next to it rather than duplicating it.

Styling

The number renders as a <span class="LinkRobinsPostNum"> in the post header, alongside the timestamp. Restyle it from your theme's custom LESS:

.LinkRobinsPostNum {
  opacity: .5;
  font-variant-numeric: tabular-nums;
}

Requirements

• Flarum 2.0 or later
• PHP 8.3 or later

What changed from the 1.x original

The original extension targeted Flarum 1.x and relied on a webpack/JSX build pipeline. This 2.0 port:

• Targets flarum/core ^2.0
• Uses the runtime extend() helper from the export registry with string-path lazy module resolution, so no JSX/build step is required
• Uses the canonical 2.0 model accessors (post.number(), post.isHidden()) with fallback to raw attribute access for resilience
• Renames the CSS class to LinkRobinsPostNum to avoid colliding with the original if both are ever installed side-by-side
• Adds tabular-numeric digit alignment so post numbers stay column-aligned in lists

Translation strings follow the same shape — the only difference is the namespace key.