I have attempted to set the text and/or page background to be less glary than the standard white.
I went in via Appearance > Editor > Text background.
The effect is now that the text sits in a jagged white area. The background colour I set on the colour wheel is round the edges only.
The ‘page background’ setting was a mid-grey and changing this didn’t seem to do anything, so I left it. I’m not sure where that mid-grey colour appears…
Can I have a steer on how to get the text sitting on a unified background colour, all over the ‘page’ or rather pane, and apologies if I have missed something obvious.
Okay, it sounds like you have the text background set correctly (page background, incidentally, is the background for the page—i.e. the texture or colour that you see around the paper area, when using Page View mode on the Mac), but all of your text also has a white highlight added to it. Try selecting the text with the jagged white background and use the highlight tool in the Format Bar to remove highlighting (right-click the colour chip and select the white box with a diagonal red slash through it).