4chan Reddit-like frontend par odiihinia

A Firefox/Chrome (Manifest V3) extension that transforms a 4chan thread into a
Reddit-style nested, collapsible comment view — replies appear indented
under the post they answer, and any subtree can be collapsed/expanded.

4chan replies can quote several posts at once, so a strict tree doesn't fit.
This extension uses full duplication: a post is shown under every in-thread
post it quotes (including OP).

• The first copy of a post renders fully expanded.
• Any duplicate copy renders collapsed with a duplicate ↑ badge; click the
  badge to jump to the first copy, or click the collapsed comment to expand it
  in place (children build lazily, so big threads stay responsive).
• A post that quotes nobody (or only dead / cross-thread posts) is treated as a
  top-level reply to the thread and placed under OP.
• Greentext, spoilers, and country flags are reused straight from 4chan's own
  rendering. The view uses a dark theme (olive page / brown cards) so greentext
  reads clearly.
• Nesting is color-coded by depth (RES-style): each indent level's thread
  line gets its own color so a single conversation is easy to follow.
• Poster handles — on /pol/-style boards every poster has a unique ID. If
  they kept the default "Anonymous" name, it's replaced with a stable, readable
  handle derived from that ID (e.g. WiredLoon07), colored by the ID's own
  color, so the same poster is easy to track. Posters with a real name are left
  as-is.
• Redundant >>NNN references are pruned from both the comment text and the
  meta line's backlink list — the nesting already shows replies. Only
  same-thread quotes are removed; cross-thread quotes (>>N →) and dead
  links (deleted posts) are kept, since the tree can't represent those.
• Inline media — click an image or .webm/.mp4 thumbnail to expand it in
  place. Both images and videos resize by dragging anywhere on them (aspect
  preserved); for videos the bottom control bar stays usable and a plain click
  toggles play/pause. A plain click on an image collapses it again (or use the
  ✕). Videos pause automatically when scrolled out of view. Image previews load
  the full image (lazily) for a crisp "at a glance" thumbnail.
• Default video volume — webms/mp4s start at a chosen level (default 50%)
  instead of full blast. Set it from the toolbar's 🔊 slider or the popup
  (the two stay in sync), and any level you pick on a video becomes the new
  default automatically.
• Gallery — the toolbar's 🖼 Gallery button opens a full-screen viewer
  over all media in the thread. Scroll, arrow keys, or the ‹ › buttons move one
  post at a time; a filter button cycles All media → Images only → Videos
  only; the original file name is shown under the counter; Esc or a backdrop
  click closes it.
• Custom theme colors — the popup has color pickers for the page
  Background and the Posts (comment box) color, with a Reset to the
  defaults. They're stored per-browser so your palette isn't universal.
• Friendlier timestamps — dates are reformatted to your locale and each
  comment shows a live "X ago" on the right, refreshed every 10 seconds.
• A faint divider separates each top-level thread (direct replies to OP).