Migration to PHP 8.1 - how to fix Deprecated Passing

[yamahdico]

Deprecated: Return type of Base::offsetexists($key) should either be compatible with ArrayAccess::offsetExists(mixed $offset): bool, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /var/www/.../vendor/bcosca/fatfree-core/base.php on line 2232

Deprecated: Return type of & Base::offsetget($key) should either be compatible with ArrayAccess::offsetGet(mixed $offset): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /var/www/.../vendor/bcosca/fatfree-core/base.php on line 2251

Deprecated: Return type of Base::offsetset($key, $val) should either be compatible with ArrayAccess::offsetSet(mixed $offset, mixed $value): void, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /var/www/.../vendor/bcosca/fatfree-core/base.php on line 2242

Deprecated: Return type of Base::offsetunset($key) should either be compatible with ArrayAccess::offsetUnset(mixed $offset): void, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /var/www/.../vendor/bcosca/fatfree-core/base.php on line 2260