Headers error

Hello,

When removing WP default displaying ‘category’ term in urls (by adding %category% as base for categories in the optional section in dashboard), no pages/posts are displayed (only archives pages), getting a 404 error.

When I remove the optional base category, all is displayed correctly.

Previously, a SEO plugin used to remove WP default term but that plugin had been removed. I´ve cleared WP and several browsers cache, not solving the issue (no cache on server side).

When removing default term (no pages/posts diplayed, only archives pages), WP Debug mode shows:

Notice: Undefined property: wpdb::$dmtable in /home/rabbitr1/public_html/wp-includes/wp-db.php on line 648

Warning: Cannot modify header information – headers already sent by (output started at /home/rabbitr1/public_html/wp-includes/wp-db.php:648) in /home/rabbitr1/public_html/wp-content/plugins/wp-super-cache/wp-cache-phase2.php on line 1379

wp-cache-phase2.php on line 1379 says:

if ( defined( ‘WPSC_VARY_HEADER’ ) ) {
if ( WPSC_VARY_HEADER != ” ) {
header( ‘Vary: ‘ . WPSC_VARY_HEADER );
}

Currently usign:

– WP v5.7.2
– the latest Hello Elementor´s theme version
– Elementor v3.2.5
– WP Super Cache 1.7.4

Why is this term removal affecting only pages/posts headers, and not those for archives?

Regards,

Julia

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