Backspace key behavior
It is a terrible thing that Backspace key supports delete characters and delete annotations. For example, you want rewrite an annotation with a new thought and delete all characters, if you hold Backspace key for deleting all characters, you will find you need to rehighlight the texts.
https://forums.zotero.org/discussion/comment/425672/#Comment_425672
Yerha, what version of zotero are you using?