Add/remove visibility(including cutom ones) and rearrange attributes in the header that currently only has Title, Username and Url

Possible Solution

For example,

1. Right Click on the Title
2. Edit
3. A new window will open that will have all shown attributes listed in Vertical way and nearby the list of ALL attributes including custom ones that you can place in there.
4. To place attributes there could simple arrows LEFT and RIGHT to place entries from one list to another, and UP and DOWN to rearrange them

Context

More visibility to things actually used. Frankly i don't think there should be a difference between custom and non custom properties, you can have those standart options simply available as default. This could result in additions to the code that won't rely on just built-ins. For example this #146 useful addition only takes into account built-in properties and thus not expandable(or atleast it looks like it from GUI screenshots in there)