It turned out that Magnet (third party window tiling app) was sometimes truncating my notes (reported here.) I reported the problem to but have received no response.
Moom is a similar app. Does anyone know if it works properly with Agenda?
I frequently need to have Agenda on half my screen and another app beside it. The native Mac way of doing this is a total pain. Magnet is wonderful apart from truncating notes, forcing me to faff around with Agenda to see the full note again. I’d love to find a working alternative!