Just to test various things. This is a classic block with Underline using ctrl-U.   

Goodness me! With Advanced Editor Tools (previously TinyMCE Advanced) one can extend and enhance the block editor (Gutenberg) and the classic editor (TinyMCE). For example add an icon for underline.

 

 ** Contact form test:

 

Click here for what a u3a_group_category page looks like without customising the category template. It could look better if we modified the template! It might be a useful feature, or maybe not.