#Pixelfed's major shortcomings, IMHO.
I realise some of these derive from the very proposition (ie, cloning #Instagram's horrible UI), and perhaps others are configurable or specific to my instance (#pixelfed.de). Still.

0️⃣ No distinction between “title” (short & descriptive; shown on media previews and thumbnails) and “description” (long text; on post pages only).
1️⃣ Images are too small (on my laptop, limited to 732 px in width); no “open largest size by default” or “full screen mode”.
2️⃣ Can't navigate between adjacent images; ie swiping or pressing →/← to move within a collection, tag, or profile.
3️⃣ Small thumbnails (mosaic on collection, tag or profile pages) don't show the (beginning of the) description.
4️⃣ Small thumbnails always indicate zero comments, even when there *are* comments.
5️⃣ Large thumbnails (entries on home page) aren't clickable; one has to click on tiny “x days ago” in footer.
6️⃣ New comments don't appear under “notifications” (/account/activity).
7️⃣ Collections are limited to 18 posts.
8️⃣ “Edit” action fails consistently.
9️⃣ Even short descriptions and comment threads are truncated/hidden (eg, 4 clicks are needed to reveal/expand everything on https://pixelfed.de/p/tripu/265782587476283392); text is squeezed in that narrow column.