Conflict with polylang

OK, I can replicate this issue irrespective of Polylang or PWA with code like this:

add_action( 'plugin_loaded', function () {
	get_posts();
} );

add_action( 'parse_query', static function ( WP_Query $query ) {
	error_log( is_404() ? 'is 404' : 'is not 404' );
} );

The issue seems to be that Polylang is querying posts before the $wp_query global is set, and that WP_Query instance that Polylang is creating is not global so then the notice is generated.

Perhaps the PWA plugin should replace the parse_query action with wp.

The code in question was introduced in PR 279.

I had two explanations for why parse_query was chosen:

• https://github.com/GoogleChromeLabs/pwa-wp/pull/279#discussion_r419172718
• https://github.com/GoogleChromeLabs/pwa-wp/pull/279#issuecomment-623679849

It seems the reason I chose parse_query is that it was the earliest possible point. But I didn’t consider if the query being parsed was the main query. I’ve opened a fix for this in https://github.com/GoogleChromeLabs/pwa-wp/pull/712

Could you try applying that change to see if it fixes the issue?

Version 0.7 will be released this week with the fix.