By default, CodeMirror makes the home and end keys navigate to the beginning

and end of the line of text, regardless of how it is wrapped. This is different

from the usual behavior of text fields, where if the text is wrapped, home/end

go to the ends of the wrapped line (i.e. the cursor stays on the same visible

line within the wrapped text).
Luckily, there's a pretty simple fix for this, as detailed at

https://github.com/codemirror/CodeMirror/issues/1576

Added some long-form text to an open CodeMirror editor and checked that

home/end now behaved as expected.