customizer_set_uri can cause depreciation notice in PHP 8.1

[thomaslhotta]

Hi

In the function customizer_set_uri on line 693 the 'query' key of $uri can be empty. If that is the case, a depreciation notice will be emitted.

I think the best solution would be to change the preceding else statement to an

else if ( ! empty( $uri['query'] ) {

because if the query key is empty the rest of the functionality does nothing anyway.