The keep text upright feature works poorly with left- or
right-justified text (it flips around the anchor point).
This is difficult to fix because it’s done at display time (so if the
code is changed it will change the layout of existing boards).
We could insert a second “keep upright” algorithm that’s done at edit
time, and would essentially disable the display-time one for edited
text (since it would already be adjusted to upright). The downside to
this is that if you rotate some text with keep-upright on, and then
turn it off, the text won’t “un-flip”. But maybe that’s not so bad?
The “keep” verb nearly already suggests that it’s an edit-time
function.
