I have created a settings page and set its parent to options-general.php
to have it under the Settings menu, then moved its submenu to the top of the Settings menu so when I click on the Settings main menu it opens it because it's now the first child of the Settings menu.
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The issue is with the URL of the Settings main menu, it's:
localhost/wp-admin/admin.php?page=settings_admins
, not:
localhost/wp-admin/options-general.php?page=settings_admins
.
Because of this, clicking the main menu will open my custom settings page, but will not highlight it as the current opened page, whereas clicking the submenu link does.
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Is it something related to WordPress or your plugin?