Highlight a markdown input in red if required and submit is pressed

Kind of copy the behaviour of a Firefox input
Once the submit button has been pressed, highlight in red the text
input if it's required but empty
2 jobs for rework-front in 35 minutes and 12 seconds (queued for 3 seconds)
Status Name Job ID Coverage
  Test
passed black #2846

00:01:44

passed test #2845

00:35:12

63.0%