MyBB Community Forums

I am upgrading from 1.6 to the latest.  Most everything is working except a few plugins. 

1) Every post isn't clickable.  You can't see the actual title of a post and all it says is "Go to the first unread post" within a thread, but on the main forums it just lists the user and time of a post but no title to click on.  Anyone know why this is happening?

2) I'm getting the MyBB internal error.  Disabled all plugins and still get it.  The error log says:

<error>
<dateline>1614463461</dateline>
<script>inc/class_parser.php</script>
<line>659</line>
<type>2</type>
<friendly_type>Warning</friendly_type>
<message>preg_replace(): Unknown modifier '0'</message>
<back_trace>#0  errorHandler->error() called at [[PHP]: ]
#1  preg_replace() called at [/inc/class_parser.php:659]
#2  postParser->parse_badwords() called at [/inc/functions_forumlist.php:308]
#3  build_forumbits() called at [/index.php:427]
</back_trace>
</error>

<error>
<dateline>1614474973</dateline>
<script>inc/class_parser.php</script>
<line>659</line>
<type>2</type>
<friendly_type>Warning</friendly_type>
<message>preg_replace(): Unknown modifier '0'</message>
<back_trace>#0  errorHandler->error() called at [[PHP]: ]
#1  preg_replace() called at [/inc/class_parser.php:659]
#2  postParser->parse_badwords() called at [/inc/functions_forumlist.php:308]
#3  build_forumbits() called at [/inc/functions_forumlist.php:154]
#4  build_forumbits() called at [/index.php:427]
</back_trace>
</error>

What version of PHP are you using? Can you list all the bad word replacements you've got set up?

PHP 5.4.45, but I changed it to 7.4 and no page loaded, it just loaded a white page with the "MyBB internal error" so I put it back to 5.4

Word Filters:
#000080 #0033CD No (regular expression)
[color=blue] [color=#0033CD] No

So those # are being picked up as regex pattern delimiters - can you try adding a \ before the # in the ACP?

We should probably do that automatically in the parsing of these to be fair.

Genuine report?