Show the pictures inside Reddit comments

A comment that was a picture rendered as either a link or, for a Giphy, the
literal text `![gif](giphy|Ve7wX45gaOFmw8eeEM)`. On r/aww that is most of the
thread.

Reddit writes an inline image as a token rather than an address, in three
shapes: `![gif](giphy|ID)` for a Giphy, `![img](emote|t5_2th52|4358)` for a
subreddit emote, and `![img](jo8gf0ca92zd1)` for an image uploaded straight to
the comment. The useful part is that all three tokens are keys in that same
comment's own `media_metadata`, so this is one lookup and not three special
cases. Nothing in the adapter has to know what Giphy is.

The fourth shape is someone pasting the address of a picture, which on Reddit
is how most images in comments actually arrive -- 117 of them against 21
Giphys in the sample I scanned. Those are shown as pictures too, decided by
the file extension. A link that is not to an image stays a link.

Animated ones take `s.gif` over `s.mp4` even though the MP4 is several times
smaller: a GIF moves on its own in an `<img>`, and an MP4 would need a player
element with autoplay, loop and muted set, for something the size of a
postage stamp.

Everything goes through the `/m/` proxy, like all other media. Without that a
comment thread would have the reader's browser fetch dozens of files straight
from Reddit, which is the one thing this whole app exists to avoid.

Placing the image is the renderer's job, not the Markdown parser's, because
the proxy is a render-time concern and markdown.ts knows nothing about it --
so it takes an optional `ImageRenderer` and, without one, an image stays a
link exactly as before. The parser also learned `![...]` proper: the link rule
was matching from the `[` and stranding the `!` as text.

Verified on r/aww/comments/171dxph, which carries one Giphy and 77 pasted
images: 35 render on the first page, all 35 load, all 35 through the proxy,
no upstream address reaches the page, no token is left unresolved, and
nothing overflows the column or scrolls the page sideways.

Co-Authored-By: Claude Opus 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_017nMQ2eDKnqALYhAibpTKTu

README.md

@@ -126,6 +126,13 @@ which is why it only appears once the script has run. What was behind a _load mo
 not fetched — that is a second page and often a third — but it is counted and said out
 loud rather than quietly dropped.
 
+Pictures inside comments are shown as pictures. Reddit writes them as a token rather
+than an address — a Giphy id, a subreddit emote, or an image uploaded to the comment —
+and all three are looked up in the comment's own metadata to find the real file. An
+image address someone simply pasted is shown too, which on Reddit is how most of them
+arrive. All of it goes through the same `/m/` proxy as everything else, so reading a
+comment thread never has your browser talking to Reddit.
+
 Media never gets linked straight at a CDN. Instagram and TikTok reject requests without
 a matching `Referer` (and sometimes cookies), and proxying keeps your browser from
 talking to the platform at all. Every asset is registered under an opaque `/m/<id>` and