I've begun to try to navigate my way around Krita.
I've been trying to understand the brush system more.
For some reason I can no longer access the brush editor.
It used to be along side the foreground and background colors and the patterns in the toolbar but has gone missing.
I've been trying all day to edit the toolbar and find a way to access it via the menu's or reinstate in it's proper place in the toolbar.
But all to no avail. Any advice?

That button is is part of the so called "Painter's Tools". You should be able to find them in the "Configure Toolbars"-dialog. If that doesn't work I'd recommend to remove Krita's config file.

Kind regards

Enabling the painters tool did the trick. Thank you kindly for taking the time to help and internet stranger out.