Mark all messages as read in sub-folders

Hi! Is there a way to mark all messages as read, including those in sub-folders?
Thanks and regards.

Go to “Menu / Settings / General” (PC) or “eM Client / Settings / General” (Mac) and tick the box “Show Favorites”.

Then save and close settings.

Next click the "Unread folder at the top left under Favourites and “Select all” messages.

Lastly “Mark as read” via either the menu or via right click.

This will then make all account primary and sub folder messages read.