Here is a list of special, unlinked pages (they may be linked in questions and answers) on Stack Exchange sites. Most pages listed here are work in progress or legacy. Currently, this list is incomplete.
If you know more of them, add them to the answer.
Related Hidden features of Stack Exchange?
/topbar/site-switcher/site-list, e.g. stackoverflow.com/topbar/site-switcher/site-list
/topbar/site-switcher/all-pinnable-sites, e.g. stackoverflow.com/topbar/site-switcher/all-pinnable-sites
{
"title":"3d printing meta",
"description":"",
"sitename":"3D Printing Meta",
"hostname":"3dprinting.meta.stackexchange.com",
"siteid":641
}
/hot-questions-for-mobile, as it was created to be used by the mobile apps to show hot questions. Since November 2022, has been relocated to its current URL, with the old URL kept as a redirect./election, e.g., stackoverflow.com/election
/error, e.g. http://stackoverflow.com/error/captcha, e.g., stackoverflow.com/captcha
/nocaptcha/nocaptcha, e.g. stackoverflow.com/nocaptcha
/404, e.g., stackoverflow.com/404/questions/greatest-hits, e.g., stackoverflow.com/questions/greatest-hits/annotated-posts, e.g., stackoverflow.com/annotated-posts/questions?filters=DeactivatedUsers, e.g. stackoverflow.com/questions?filters=DeactivatedUsers
/home/recommended/debug, e.g. stackoverflow.com/home/recommended/debug
/home/get-jquery-fallback-cookie, e.g. stackoverflow.com/home/get-jquery-fallback-cookie
ajax.googleapis.com. Sets a cookie on one's browser to load the scripts from another source./questions/ask/advice, e.g. stackoverflow.com/questions/ask/advice
/questions/ask?tags=[tag names separated by +], e.g. stackoverflow.com/questions/ask?tags=javascript+html/?tab=active, e.g. stackoverflow.com/?tab=active
?questions&tab=active (although that also works)./users/flair/[user ID], e.g. https://stackoverflow.com/users/flair/1
/users/flair/[user ID].json, e.g. https://stackoverflow.com/users/flair/1.json
/users/flair/[user ID].js, e.g. https://stackoverflow.com/users/flair/1.js
For the items in this section, you must be logged in, and you get the data corresponding to your account.
/reputation, e.g., stackoverflow.com/reputation
/topbar/inbox, e.g. stackoverflow.com/topbar/inbox (same content on any site)
/topbar/achievements, e.g. stackoverflow.com/topbar/achievements
/users/tag-future/current, e.g., stackoverflow.com/users/tag-future/current
https://stackexchange.com/users/[network account ID]/?tab=flair, e.g. https://stackexchange.com/users/current/?tab=flair
/users/flag-summary/current?showDeclined=true e.g., meta.stackexchange.com/users/flag-summary/current?showDeclined=true
/users/flag-summary/current
/help/privileges/user/[user ID], e.g. https://cooking.stackexchange.com/help/privileges/user/86/posts/[post ID]/revisions, e.g., meta.stackexchange.com/posts/76569/revisions
/posts/[post ID]/votes, e.g. meta.stackexchange.com/posts/74983/votes
/posts/[post ID]/vote-counts, e.g. meta.stackexchange.com/posts/74983/vote-counts
null./posts/[post ID]/comments, e.g. meta.stackexchange.com/posts/74983/comments
/posts/[post ID]/body, e.g. meta.stackexchange.com/posts/74983/body
/posts/[post ID]/edit-inline, e.g. meta.stackexchange.com/posts/74983/edit-inline
/posts/[post ID]/edit-tags, e.g. meta.stackexchange.com/posts/74983/edit-tags
/posts/[post ID]/ajax-load, e.g. meta.stackexchange.com/posts/74983/ajax-load
/review/[review type]/[review ID], e.g., stackoverflow.com/review/suggested-edits/5375800
/posts/comments/[comment ID], e.g. stackoverflow.com/posts/comments/1612336
https://stackoverflow.com/questions/1732348/regex-match-open-tags-except-xhtml-self-contained-tags/1732454#comment1612336_1732454, the comment ID is 1612336. Replace the "[comment ID]" in the above template with that.&page={N} to the end of the URL./rooms/pingable/[room number] e.g. chat.meta.stackexchange.com/rooms/pingable/89
chat.stackexchange.com/message/<message_id>; e.g. chat.stackexchange.com/message/32533704 is the raw HTML of this message.
?plain=true to the end of the URL, you get raw Markdown (see below)chat.stackexchange.com/messages/<room_id>/<message_id>; e.g. chat.stackexchange.com/messages/240/32533704 is what the user that posted this message typed.
chat.stackexchange.com/message/<message_id>?plain=truechat.stackexchange.com/account/<network_profile_id>; e.g. chat.stackexchange.com/account/1 redirects to the chat profile of stackexchange.com/users/1
/admin/recent-flags - Per-server basic list of messages flagged.
/404 is actually an unlinked page, rather than just a non-existent page that therefore gives a 404 error?
Commented
Sep 25, 2012 at 10:43
/annotated-posts) is actually linked from the /admin/links page (as I've just been informed), but that latter links page is only visible to mods even though the annotated posts page is visible to everyone.
/election page is actually linked from the badge descriptions (I guess it should also be linked somewhere else on a site during election so people could participate easily). Also 5 of these links can be accessed freely through a top/side bar (and 1 through comments), so there's not much point in them. And the tag prediction doesn't seem to work.
Commented
May 3, 2021 at 13:50