Hello,
I have been happily using the Joomlabamboo template Corporate for a number of years.
I have attempted to update my php from 5.6 to 7.3 and it is crashing the template with the error below.

Can someone suggest how i best fix these errors? is there an update to the template/modules I can easily use?

Many thanks!
0 - Using $this when not in object context
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Using $this when not in object context
/homepages/7/d175440996/htdocs/psychologicalminds/templates/corporate/framework/classes/zen.php:425

Call stack

Function Location

1 () JROOT/templates/corporate/framework/classes/zen.php:425
2 Zen::togglemenu() JROOT/templates/corporate/index.php:51
3 require() JROOT/libraries/src/Document/HtmlDocument.php:668
4 Joomla\CMS\Document\HtmlDocument->loadTemplate() JROOT/libraries/src/Document/HtmlDocument.php:730
5 Joomla\CMS\Document\HtmlDocument->fetchTemplate() JROOT/libraries/src/Document/HtmlDocument.php:545
6 Joomla\CMS\Document\HtmlDocument->parse() JROOT/libraries/src/Application/CMSApplication.php:1030
7 Joomla\CMS\Application\CMSApplication->render() JROOT/libraries/src/Application/SiteApplication.php:778
8 Joomla\CMS\Application\SiteApplication->render() JROOT/libraries/src/Application/CMSApplication.php:202
9 Joomla\CMS\Application\CMSApplication->execute() JROOT/index.php:49