I see a Fatal Error when I activate Toolset Blocks:
Fatal error: Class ToolsetBlocksBlockStyleBlockHeading contains 1 abstract method and must therefore be declared abstract or implement the remaining methods (ToolsetCommonEsBlockStyleBlockAPartlyWithConfig::print_base_css) in /path/to/site/wp-content/plugins/toolset-blocks/vendor/toolset/blocks/server/Block/Style/Block/Heading.php on line 13
Okay I was able to create a site clone and install it locally on my own test environment. There were a few data serialization notices, but most of those were options-table related and don't seem relevant to the problems here. I disabled WP Rocket and the Popup maker plugins during the clone installation process. Then in wp-config.php I commented out the WP_Cache line added by WP Rocket and turned on PHP error logs temporarily.
After that, I was able to log in from the custom login URL and reproduce the Fatal Error on the /registration page immediately. So I temporarily deactivated all plugins (including the advanced-cache.php drop-in and the must-use plugin) and activated the default Twenty Twenty One theme. Then I deactivated and deleted Types, Blocks and Forms from Plugins > Installed Plugins.
Next I downloaded a fresh copy of Types 3.4.8 from https://toolset.com/account/downloads and installed that new copy in wp-admin > Plugins > Add New. Then I unregistered and re-registered Toolset in Plugins > Add New > Commercial tab (you should not have to do this on the live site, I just wanted to be able to use the automatic installer in my local environment). I clicked "Check for Updates" in the Toolset installer panel to install and activate the latest versions of Blocks and Forms.
At that point, I went back to the front-end /registration page and saw a complete page rendered. No fatal errors appeared in the logs, so I reactivated the custom theme and all other plugins that were previously active (including the drop-in and must-use plugin). Still no fatal errors, but numerous PHP notices begin appearing at that point in the logs. With only Toolset plugins active, those notices are not thrown.
So I think that's what I would try next on the live site. You've already updated WP, but the Toolset plugins are not all up-to-date. I would try deactivating and deleting Types, Blocks and Forms completely from Plugins > Installed Plugins. Then temporarily deactivate all other plugins and activate a default theme like Twenty Twenty One. Install and activate a fresh copy of Types 3.4.8 downloaded from your Toolset account area here https://toolset.com/account/downloads, then use the automatic installer to install and activate the latest versions of Blocks and Forms. Then check the /registration page and ensure the fatal error is resolved. If so, reactivate your custom theme and other plugins. If the fatal errors reappear, deactivate everything except Toolset again and iteratively reactivate components until the problem returns, but I suspect the issue is resolved by updating Toolset plugins to their latest versions.
You were right, even though the plugins did not show that there was an update on the plugins page when I went to the registration page and hit "check for updates" then I was able to download the newest and that solved the problem.
My issue is resolved now. Thank you!
