Thanks Sofy. I have already translated the WPForo, by pressing "Edit" in Loco translate and then it has saved it in "AUTHOR"./p> Does this mean I have...

@robert Thank you for explanation. Will it also be lost, when I use a Child theme? Thank you for helping me out! 

@robert Thank you. I'm not sure why it is the wrong way? I followed this explanation/p>

Thank you. Do I need recaptcha when I have user registration and they need to activate account by a link in their email? Will bots be able to both...