Parsing user options fails if not using browser extension

[mvaaltola]

Background

I'm using Todoist in Rambox which doesn't support browser extensions but allows users to inject their own JavaScript. For this reason I'm bundling your wonderful extension to a minified js file:

cat src/mousetrap.js > build.js
cat src/todoist-shortcuts.js >> build.js
uglifyjs build.js > build-min.js

This has worked perfectly, but some time ago after upgrading from around version 135 to the latest v164 I started noticing an annoying issue.

The issue

After upgrading I noticed that the cursor disappears after marking tasks as done. For a while I worked around this by manually selecting another task or changing the task list, but eventually started looking for the cause.

I located the issue to loadOptions. If document.body.getAttribute('data-todoist-shortucts-options') returns null (which it will since I don't have the browser extension installed), the default empty options array is overwritten with JSON.parse(null), i.e. null. This in turn results in uncaught TypeErrors in both getXOption functions which expect options to be an object.

I'll submit a oneliner PR that has fixed this issue for me. Thanks again for the great extension!