Steps to reproduce:
1) Place the cursor on a new empty line at the bottom of the note
2) Press 3 times on the key - (or *)
-> A separating line is created. But it still appears in blue.
https://s3.amazonaws.com/zotero.org/images/forums/u265723/l0ce3pmyithm80juey7t.png
3) Press again the key - (or any other letter key)
-> The line is deleted and replaced by the newly added character.

I would expect that the line is not selected after being created, and the cursor moved to below the line, showing this:
https://s3.amazonaws.com/zotero.org/images/forums/u265723/m8z7m56xwvab2ps8060k.png

Debug ID: D1413290674
Zotero 7.0.0-beta.117+794dc6bf0 (64-bit)
Windows 10

If I do the same with a line below the newly added separating line, it directly goes to the next line after making the line:
https://s3.amazonaws.com/zotero.org/images/forums/u265723/xcbh2d84gdslb768763h.png

Other remark:
When selecting text, the separating line does not appear as selected
https://s3.amazonaws.com/zotero.org/images/forums/u265723/58fvoxikbn3aybpw18tt.png