diff --git a/pagure/pfmarkdown.py b/pagure/pfmarkdown.py
index 363e94b..9fe6ddf 100644
--- a/pagure/pfmarkdown.py
+++ b/pagure/pfmarkdown.py
@@ -22,8 +22,10 @@ Author: Ralph Bean <rbean@redhat.com>
 import flask
 
 import markdown.inlinepatterns
+import markdown.preprocessors
 import markdown.util
 import pygit2
+import re
 
 import pagure.lib
 from pagure.config import config as pagure_config
@@ -51,7 +53,10 @@ COMMIT_LINK_RE = \
     '([a-zA-Z0-9_-]*?/)?'\
     '([a-zA-Z0-9_-]+)'\
     '#(?P<id>[\w]{40})'
-IMPLICIT_ISSUE_RE = r'(?<!\w)#([0-9]+)'
+# PREPROCIMPLLINK is used by ImplicitIssuePreprocessor to replace the
+# '#' when a line starts with an implicit issue link, to prevent
+# markdown parsing it as a header; we have to handle it here
+IMPLICIT_ISSUE_RE = r'(?<!\w)(?:PREPROCIMPLLINK|#)([0-9]+)'
 IMPLICIT_PR_RE = r'(?<!\w)PR#([0-9]+)'
 IMPLICIT_COMMIT_RE = r'(?<![<\w#])([a-f0-9]{7,40})'
 STRIKE_THROUGH_RE = r'~~(.*?)~~'
@@ -151,6 +156,51 @@ class CommitLinkPattern(markdown.inlinepatterns.Pattern):
         return text
 
 
+class ImplicitIssuePreprocessor(markdown.preprocessors.Preprocessor):
+    """
+    Preprocessor which handles lines starting with an implicit
+    link. We have to modify these so that markdown doesn't interpret
+    them as headers.
+    """
+    def run(self, lines):
+        """
+        If a line starts with an implicit issue link like #152,
+        we replace the # with PREPROCIMPLLINK. This prevents markdown
+        parsing the line as a header. ImplicitIssuePattern will catch
+        and parse the text later. Otherwise, we change nothing.
+        """
+        # match a # character, then any number of digits
+        regex = re.compile(r'#([0-9]+)')
+        new_lines = []
+        for line in lines:
+            # avoid calling the regex if line doesn't start with #
+            if line.startswith('#'):
+                match = regex.match(line)
+                if match:
+                    idx = int(match.group(1))
+                    # we have to check if this is a real issue or PR now.
+                    # we can't just 'tag' the text somehow and leave it to
+                    # the pattern to check, as if it's *not* one we want
+                    # the line treated as a header, so we need the block
+                    # processor to see it unmodified.
+                    try:
+                        namespace, repo, user = _get_ns_repo_user()
+                    except RuntimeError:
+                        # non-match path, keep original line
+                        new_lines.append(line)
+                        continue
+                    if (
+                        _issue_exists(user, namespace, repo, idx) or
+                        _pr_exists(user, namespace, repo, idx)
+                    ):
+                        # tweak the text
+                        new_lines.append('PREPROCIMPLLINK' + line[1:])
+                        continue
+            # this is a non-match path, keep original line
+            new_lines.append(line)
+            continue
+        return new_lines
+
 class ImplicitIssuePattern(markdown.inlinepatterns.Pattern):
     """ Implicit issue pattern. """
 
@@ -275,6 +325,8 @@ class PagureExtension(markdown.extensions.Extension):
         ])
         markdown.inlinepatterns.AUTOLINK_RE = AUTOLINK_RE
 
+        md.preprocessors['implicit_issue'] = ImplicitIssuePreprocessor()
+
         md.inlinePatterns['mention'] = MentionPattern(MENTION_RE)
 
         md.inlinePatterns['implicit_commit'] = ImplicitCommitPattern(
diff --git a/tests/test_pagure_lib.py b/tests/test_pagure_lib.py
index 654b1ef..8d20c89 100644
--- a/tests/test_pagure_lib.py
+++ b/tests/test_pagure_lib.py
@@ -4078,9 +4078,13 @@ class PagureLibtests(tests.Modeltests):
         watch_list = [obj.name for obj in watch_list_objs]
         self.assertEqual(watch_list, [])
 
+    @patch('flask.request.url', 'http://pagure.org/test/issue/69')
+    @patch('flask.request.url_root', 'http://pagure.org/')
+    @patch('flask.request.args.get', return_value=None)
+    @patch('flask.request')
     @patch('flask.g')
     @patch('pagure.lib.notify.send_email', MagicMock(return_value=True))
-    def test_text2markdown(self, g):
+    def test_text2markdown(self, g, req, reqget):
         ''' Test the test2markdown method in pagure.lib. '''
         pagure.config.config['TESTING'] = True
         pagure.config.config['SERVER_NAME'] = 'pagure.org'
@@ -4093,8 +4097,22 @@ class PagureLibtests(tests.Modeltests):
         # PR#1 to project test
         self.test_new_pull_request()
 
-        # create PR#2 to project pingou/test
+        # create an issue (will be #2) in 'test' project
         repo = pagure.lib._get_project(self.session, 'test')
+        iss = pagure.lib.new_issue(
+            issue_id=2,
+            session=self.session,
+            repo=repo,
+            title='test issue',
+            content='content test issue',
+            user='pingou',
+            ticketfolder=None,
+        )
+        self.session.commit()
+        self.assertEqual(iss.id, 2)
+        self.assertEqual(iss.title, 'test issue')
+
+        # create PR#2 to project pingou/test
         forked_repo = pagure.lib._get_project(self.session, 'test', user='pingou')
         req = pagure.lib.new_pull_request(
             requestid=2,
@@ -4197,6 +4215,12 @@ class PagureLibtests(tests.Modeltests):
             'test#1 bazinga!',
             'pingou opened the PR forks/pingou/test#2',
             'fork/pingou/ns/test#8 is private',
+            'implicit link to #1',
+            'implicit link .#1. with non-whitespace, non-word characters',
+            '#2 - implicit link at start of line',
+            '#2. implicit link at start of line with no whitespace after',
+            '#regular header',
+            '#34 looks like an implicit link, but no issue 34',
             'pingou committed on test#9364354a4555ba17aa60f0dc844d70b74eb1aecd',
             'irc://pagure.io',
             'ircs://pagure.io',
@@ -4245,6 +4269,18 @@ class PagureLibtests(tests.Modeltests):
             # 'fork/pingou/ns/test#8 is private',
             '<p><a href="http://pagure.org/fork/pingou/ns/test/issue/8" '
             'title="Private issue">pingou/ns/test#8</a> is private</p>',
+            # 'implicit link to #1',
+            '<p>implicit link to <a href="http://pagure.org/test/pull-request/1" title="[Open] test pull-request">#1</a></p>',
+            # 'implicit link .#1. with non-whitespace, non-word characters',
+            '<p>implicit link .<a href="http://pagure.org/test/pull-request/1" title="[Open] test pull-request">#1</a>. with non-whitespace, non-word characters</p>',
+            # '#2 - implicit link at start of line',
+            '<p><a href="http://pagure.org/test/issue/2" title="[Open] test issue">#2</a> - implicit link at start of line</p>',
+            # '#2. implicit link at start of line with no whitespace after',
+            '<p><a href="http://pagure.org/test/issue/2" title="[Open] test issue">#2</a>. implicit link at start of line with no whitespace after</p>',
+            # '#regular header',
+            '<h1>regular header</h1>',
+            # '#34 looks like an implicit link, but no issue 34',
+            '<h1>34 looks like an implicit link, but no issue 34</h1>',
             # 'pingou committed on test#9364354a4555ba17aa60f0dc844d70b74eb1aecd',
             '<p>pingou committed on <a href="http://pagure.org/'
             'test/c/9364354a4555ba17aa60f0dc844d70b74eb1aecd" '