Mantis Bug Tracker - Forums

We would like to get rid of rows, that we never use to declutter the user interface:
This would help needing to scroll down to the most used "Add note" area.

There are no configuration options to get what you want.
You would have to change original source code of Mantis or to write a plugin.

BTW, I am quite sure you do not want to remove the marked "Activities" as you will see no notes and attachments when removing it.

You could do it in the CSS. Each of those elements has a unique ID like "relationships". I added a custom CSS file through my config file and added display: none to other elements I wanted to hide.