MyBB Hacks

I recently upgraded my board to MyBB 1.8.6.  Everything with XThreads seems to work fine except for some prefix filter links I have on one of my forums.  Here is the error I get when clicking those links:

SQL Error:
1054 - Unknown column 'prefix' in 'where clause'
Query:
SELECT DISTINCT tid,uid FROM mybb_posts WHERE uid='1' AND tid IN (21896,21883,21747,21742,21719,21673,21672,21630,21614,21587,21556,21429,21425,21373,21362,21332,212​88,21284,21059,20997,20842,20840,20744,20357,20241,15365,13707) AND visible IN (-1,0,1) AND `prefix` IN (5)


An example of one of the links that causes that error to appear is this link:
/forumdisplay.php?fid=18&filterxt_prefix=5

The error only happens while logged in.  For some reason, if I'm viewing as a guest, the links work correctly.

Before updating to MyBB 1.8.6, they all worked perfectly.  After I upgraded to MyBB 1.8.6, I also made sure to upgrade XThreads yesterday just to see if that would help.  The error remained even after updating XThreads.

How can I fix this?  I am comfortable editing core files if you have some find/replace instructions I can follow.  Thanks.

For 1.8, instead of using filterxt_prefix=5, use prefix=5

Thank you.  When I try that, it works for a single prefix URL.

But for the multiple prefix URLs it still doesn't work how it used to.  For example:

forumdisplay.php?fid=18&prefix[]=5&prefix[]=7

^That doesn't filter 5 and 7 like it should.

What is the new way to write the URL for multiple prefixes?

Are you using the default MyBB thread prefix?
If so, for temporary solutions, try to set the Use 'dot' Icons setting in Forum Display Options settings group to Off

That worked.  The single prefix URLs and the multiple prefix URLs all function perfectly again using filterxt_prefix=.  Thank you for the quick help.