EE Matrix filepicker error: Cannot read property 'rows' of null

Question

I'm getting the following error when opening the file picker in a Matrix field. It's broken the keyword search box and pagination within the file picker.

TypeError: Cannot read property 'rows' of null
http://www.example.org/admin.php?S=0&D=cp&C=javascript&M=combo_load&ui=datepicker,resizable,draggable,droppable&plugin=tmpl,ee_table,ee_filebrowser,ee_fileuploader,markitup,toolbox.expose,overlay,ee_url_title&file=cp/publish,cp/date,files/publish_fields,cp/publish_tabs,cp/publish_admin&v=1386674008:263

EE v2.7.3 Matrix v2.6.1

Update #1:

It seems the error is caused by the following PHP error:

A PHP Error was encountered
Severity: Notice
Message: Undefined offset: 0
Filename: libraries/Filemanager.php
Line Number: 882

Update #2

Here's the line responsible for the error:

$dirs = $this->directories(FALSE, TRUE);
$dir = $dirs[$params['dir_id']]; // error occurs here

The definition of $this->directories is as follows:

function directories($ajax = FALSE, $return_all = FALSE, $ignore_site_id = FALSE)

Seems odd that it's passing $ajax as FALSE when it's being called by ajax. Could this be the problem?

Answer 1

Have you tried updating to the latest version of Matrix? Perhaps it's a compatibility issue. https://docs.pixelandtonic.com/matrix/changelog.html