Filter Hook: This filter allows overriding `$main_tags`. Which is used in main email template.

Filter Hook: Allows filtering email template after its prepared, passed be reference.

Filter Hook: No description

Action Hook: Hook triggered before an email added to current sending list.

Action Hook: Action triggered after adding email template tag.

Action Hook: No description

Filter Hook: This filter is documented in widgets/question_stats.php

Filter Hook: No description

Action Hook: This action can be used to show custom message before category page.

Filter Hook: Filter applied before getting categories.