diff --git a/filter/tex/filtersettings.php b/filter/tex/filtersettings.php
index 34bfdd4b086..417ab400eda 100644
--- a/filter/tex/filtersettings.php
+++ b/filter/tex/filtersettings.php
@@ -5,10 +5,9 @@ require_once($CFG->dirroot.'/filter/tex/lib.php');
 $items = array();
 $items[] = new admin_setting_heading('filter_tex_latexheading', get_string('latexsettings', 'admin'), '');
 $items[] = new admin_setting_configtextarea('filter_tex_latexpreamble', get_string('latexpreamble','admin'),
-               '', " \\usepackage[latin1]{inputenc}\n \\usepackage{amsmath}\n \\usepackage{amsfonts}\n \\RequirePackage{amsmath,amssymb,latexsym}\n");
+               '', "\\usepackage[latin1]{inputenc}\n\\usepackage{amsmath}\n\\usepackage{amsfonts}\n\\RequirePackage{amsmath,amssymb,latexsym}\n");
 $items[] = new admin_setting_configtext('filter_tex_latexbackground', get_string('backgroundcolour', 'admin'), '', '#FFFFFF');
 $items[] = new admin_setting_configtext('filter_tex_density', get_string('density', 'admin'), '', '120', PARAM_INT);
-$items[] = new admin_setting_configtext('filter_tex_density', get_string('density', 'admin'), '', '120', PARAM_INT);
 
 if (PHP_OS=='Linux') {
     $default_filter_tex_pathlatex   = "/usr/bin/latex";
diff --git a/lib/db/upgrade.php b/lib/db/upgrade.php
index ddf745e98b4..06026806073 100644
--- a/lib/db/upgrade.php
+++ b/lib/db/upgrade.php
@@ -3029,6 +3029,16 @@ WHERE gradeitemid IS NOT NULL AND grademax IS NOT NULL");
         }
         upgrade_main_savepoint($result, 2010020300);
     }
+
+    // MDL-21407. Trim leading spaces from default tex latexpreamble causing problems under some confs
+    if ($result && $oldversion < 2010020301) {
+        if ($preamble = $CFG->filter_tex_latexpreamble) {
+            $preamble = preg_replace('/^ +/m', '', $preamble);
+            set_config('filter_tex_latexpreamble', $preamble);
+        }
+        upgrade_main_savepoint($result, 2010020301);
+    }
+
     return $result;
 }
 
diff --git a/version.php b/version.php
index f3cf32ee247..28952d28c0e 100644
--- a/version.php
+++ b/version.php
@@ -6,7 +6,7 @@
 // This is compared against the values stored in the database to determine
 // whether upgrades should be performed (see lib/db/*.php)
 
-    $version = 2010020300;  // YYYYMMDD   = date of the last version bump
+    $version = 2010020301;  // YYYYMMDD   = date of the last version bump
                             //         XX = daily increments
 
     $release = '2.0 dev (Build: 20100203)';  // Human-friendly version name