ver 1.15.32 causes warnings in admin panel

Hi.

FormMaker is producing a warning in the admin panel which is causing other processes (eg batch processing from other plugins, plugin updates etc) to fail due to unexpected data being returned.

Deprecated: strpos(): Passing null to parameter #1 ($haystack) of type string is deprecated in /home/sites/{domain redacted}.com/public_html/wp-includes/functions.php on line 7329 Deprecated: str_replace(): Passing null to parameter #3 ($subject) of type array|string is deprecated in /home/sites/{domain redacted}.com/public_html/wp-includes/functions.php on line 2189 Deprecated: strpos(): Passing null to parameter #1 ($haystack) of type string is deprecated in /home/sites/{domain redacted}.com/public_html/wp-includes/functions.php on line 7329 Deprecated: str_replace(): Passing null to parameter #3 ($subject) of type array|string is deprecated in /home/sites/{domain redacted}.com/public_html/wp-includes/functions.php on line 2189

(I redacted the domain for security reasons) The warning isn’t very helpful, I’m afraid. I see this on more than one site. All other plugins and wordpress are up to date. Also happening on a site with minimal other plugins, so not so likely to be a clash.

Running PHP8.1

Disabling Form maker stops the warning appearing. Disabling othe rplugins does NOT cause the warngn to disappear.