New Highlight/Ignore rules should be enabled by default

Test case

Steps

1. Open overflow menu → Core Settings → Highlights or Ignore List
2. Add a new highlight, highlight ignore rule, or ignore rule

Expected

Enabled is set to true by default, so the rule will apply upon saving.

Actual

Enabled is set to false by default, so you have to remember to separately enable the rule. Easy enough, but a possible gotcha.