add sources of 3rd-party extensions to the FAQ

Fixes #2103

doc_src/faq.hdr

@@ -24,6 +24,7 @@
 - <a href='#faq-greeting'>How do I change the greeting message?</a>
 - <a href='#faq-history'>Why doesn't history substitution ("!$" etc.) work?</a>
 - <a href='#faq-uninstalling'>How do I uninstall fish?</a>
+- <a href='#faq-third-party'>Where can I find extra tools for fish?</a>
 
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@@ -220,6 +221,18 @@ rm -f fish fish_indent
 
 Fish reserves the <a href="http://www.unicode.org/faq/private_use.html">Unicode private-use character range</a> from U+F600 thru U+F73F for internal use. Any attempt to feed characters in that range to fish will result in them being replaced by the Unicode "replacement character" U+FFFD. This includes both interactive input as well as any file read by fish (but not programs run by fish).
 
+<hr>
+\section faq-third-party Where can I find extra tools for fish?
+
+The fish user community extends fish in unique and useful ways via scripts that aren't always appropriate for bundling with the fish package. Typically because they solve a niche problem unlikely to appeal to a broad audience. You can find those extensions, including prompts, themes and useful functions, in various third-party repositories. These include:
+
+- <a href="https://github.com/fisherman/fisherman">Fisherman</a>
+- <a href="https://github.com/tuvistavie/fundle">Fundle</a>
+- <a href="https://github.com/oh-my-fish/oh-my-fish">Oh My Fish</a>
+- <a href="https://github.com/justinmayer/tacklebox">Tacklebox</a>
+
+This is not an exhaustive list and the fish project has no opinion regarding the merits of the repositories listed above or the scripts found therein. We mention these only because you may find within them a solution to a need you have such as supporting the `&&` and `||` operators or improved integration with other tools that you use.
+
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