Customize not working in Sydney Child theme

Hello! After updating to WordPress 5.8 I can no longer access the Customize functionality in the Dashboard. I get an error message that reads “There has been a critical error on this website. Please check your site admin email inbox for instructions.” No other issues at this time on the site. I haven’t found a current solution to this issue. Any assistance would be much appreciated!


First thanks for using our theme and sorry for the delay here!

We couldn’t reproduce the same issue here. I have a installation with Sydney + Sydney Child + WP 5.8 workiing normally here.

As I couldn’t reproduce the same issue in my tests here. That seems to be caused by some extra plugin you have. In this case my suggestion for you is install this plugin Health Check & Troubleshooting – WordPress plugin | and enabled the Troubleshooting Mode. With plugin activated go to Admin Dashboard > Tools > Site Health and enable the troubleshooting mode by clicking in the blue button.

This way your website will “reset” by disabling all plugins and the active theme. But note this occurs only for logged users. Then, activate the Sydney Child theme again and test if the problem still persists. You can also enable the plugins one by one to discover what’s the plugin causing the issue.

We hope this helps!

Please try that and let us know if you need further help.

Kind Regards,


aThemes Support