[doc] fix missing link in `default_http_headers` description

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>
Format: reST

.github/workflows/integration.yml

@@ -27,7 +27,6 @@ jobs:
     strategy:
       matrix:
         python-version:
-          - "3.9"
           - "3.10"
           - "3.11"
           - "3.12"

docs/admin/settings/settings_server.rst

@@ -55,11 +55,21 @@
 
 .. _method:
 
-``method`` : ``$SEARXNG_METHOD``
-  Whether to use ``GET`` or ``POST`` HTTP method when searching.
+``method`` : ``GET`` | ``POST``
+  HTTP method.  By defaults ``POST`` is used / The ``POST`` method has the
+  advantage with some WEB browsers that the history is not easy to read, but
+  there are also various disadvantages that sometimes **severely restrict the
+  ease of use for the end user** (e.g. back button to jump back to the previous
+  search page and drag & drop of search term to new tabs do not work as
+  expected .. and several more).  We had a lot of long discussions about the
+  *pros v2 cons*:
+
+  - `set HTTP GET method by default
+    <https://github.com/searxng/searxng/pull/3619>`__
+  - `http methods GET & POST
+    <https://github.com/search?q=repo%3Asearxng%2Fsearxng+label%3A%22http+methods+GET+%26+POST%22>`__
 
 .. _HTTP headers: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers
 
 ``default_http_headers`` :
-  Set additional HTTP headers, see `#755 <https://github.com/searx/searx/issues/715>`__
-
+  Set additional `HTTP headers`_, see `#755 <https://github.com/searx/searx/issues/715>`__

searx/settings.yml

@@ -100,8 +100,9 @@ server:
   image_proxy: false
   # 1.0 and 1.1 are supported
   http_protocol_version: "1.0"
-  # POST queries are more secure as they don't show up in history but may cause
-  # problems when using Firefox containers.
+  # POST queries are "more secure!" but are also the source of hard-to-locate
+  # annoyances, which is why GET may be better for end users and their browsers.
+  # see https://github.com/searxng/searxng/pull/3619
   # Is overwritten by ${SEARXNG_METHOD}
   method: "POST"
   default_http_headers: