Describe the bug
Since a few weeks (but not immediately after updating to 1.19.2) I get the following error when trying to update feed via CLI as described in the CLI Readme and in the docs.

./cli/actualize-user.php --user $user leads to

FreshRSS actualizing user “$user”…
PHP Fatal error:  Uncaught TypeError: Return value of phpQueryObject::matchClasses() must be of the type bool, none returned in /var/www/FreshRSS/lib/lib_phpQuery.php:1742
Stack trace:
#0 /var/www/FreshRSS/lib/lib_phpQuery.php(1793): phpQueryObject->matchClasses()
#1 /var/www/FreshRSS/lib/lib_phpQuery.php(1916): phpQueryObject->runQuery()
#2 /var/www/FreshRSS/app/Models/Entry.php(482): phpQueryObject->find()
#3 /var/www/FreshRSS/app/Models/Entry.php(508): FreshRSS_Entry::getContentByParsing()
#4 /var/www/FreshRSS/app/Models/Feed.php(475): FreshRSS_Entry->loadCompleteContent()
#5 /var/www/FreshRSS/app/Controllers/feedController.php(381): FreshRSS_Feed->loadEntries()
#6 /var/www/FreshRSS/cli/actualize-user.php(21): FreshRSS_feed_Controller::actualizeFeed()
#7 {main}
  thrown in /var/www/FreshRSS/lib/lib_phpQuery.php on line 1742

Feeds are not updated.
Same Problem occurs when using ./app/actualize_script.php; Updating feeds via the web however still works.

To Reproduce
Steps to reproduce the behavior:

1. Update feeds via actualize_script.php or actualize-user.php.
2. See error.

Expected behavior
Feed update script finishes without errors, only displaying notices about invalid feeds.

Environment information (please complete the following information):

• Ubuntu 18.05
• FreshRSS 1.19.2
• MariaDB 10.5.15
• PHP 7.4
• Manual Installation

Additional context

• I recently started using CSS selectors. Might be related, might be coincidence.
• I noticed lib_phpQuery.php got replaced on the edge branch, so this issue might already be fixed with the next release.