Describe the bug
When exporting annotation with Flashcard, the JSON line is undefined

    },
    undefined,
    {

To Reproduce
Steps to reproduce the behavior:

1. Annotate a line of text
2. Add a Flashcard with data on back and front
3. Export annotation as JSON
4. Search "undefined" you should get to that badly exported entry

Expected behavior

Fla

Here's an interesting one...

<a href="#linktarget">Link</a> works.

<a href="#linktarget(thing)">Link</a> doesn't work.

Adding brackets into the link target breaks the link in the PDF (works in Chrome).