A Unity ID allows you to buy and/or subscribe to Unity products and services, shop in the Asset Store and participate in the Unity community.
Separate names with a comma.
I'm aware and trying to get the solution out asap, we had a small block on pushing fixes, last two day's or so while we're updating the forum. But...
There definitely is room to improve the mobile version I agree, not being able to scroll properly is perhaps not the best thing on a forum, But I...
Login button - menu, top right under the "user" icon, if I'm not mistaken.