Exception encountered, of type &quot;Error&quot;<br />
[a81d802b] /api.php?action=rollback&amp;title=Main%20Page&amp;user=192.0.2.5&amp;token=123ABC&amp;summary=Reverting%20vandalism&amp;markbot=1   Error from line 653 of /mnt/web107/e3/91/5564191/htdocs/includes/exception/MWExceptionHandler.php: Class 'FormatJson' not found<br />
Backtrace:<br />
#0 /mnt/web107/e3/91/5564191/htdocs/includes/exception/MWExceptionHandler.php(241): MWExceptionHandler::logError()<br />
#1 /mnt/web107/e3/91/5564191/htdocs/includes/AutoLoader.php(90): MWExceptionHandler::handleError()<br />
#2 /mnt/web107/e3/91/5564191/htdocs/includes/AutoLoader.php(90): require()<br />
#3 [internal function]: AutoLoader::autoload()<br />
#4 /mnt/web107/e3/91/5564191/htdocs/includes/api/ApiFormatJson.php(78): spl_autoload_call()<br />
#5 /mnt/web107/e3/91/5564191/htdocs/includes/api/ApiMain.php(1385): ApiFormatJson-&gt;execute()<br />
#6 /mnt/web107/e3/91/5564191/htdocs/includes/api/ApiMain.php(505): ApiMain-&gt;printResult()<br />
#7 /mnt/web107/e3/91/5564191/htdocs/includes/api/ApiMain.php(436): ApiMain-&gt;handleException()<br />
#8 /mnt/web107/e3/91/5564191/htdocs/includes/api/ApiMain.php(405): ApiMain-&gt;executeActionWithErrorHandling()<br />
#9 /mnt/web107/e3/91/5564191/htdocs/api.php(88): ApiMain-&gt;execute()<br />
#10 {main}<br />