The history could be formatted as CSV, but this requires escaping the
separator in the fields and doesn't work with paths and titles with
newlines. Or as JSON, but it is inefficient to reread and rewrite the
whole history on each new file, and doing so overwrites the history with
an empty file when writing without disk space left. So this uses a
hybrid of one JSON object per line to get the best of both worlds. This
is called NDJSON or JSONL.
Co-authored-by: Kacper Michajłow <kasper93@gmail.com>