New issue background color can be confusing

Problem

The green background on the issues list page can be confusing. For example, in this screenshot there are three issues created 17 hours ago, but one of them isn't highlighted:

Relevant Slack threads:

https://gitlab.slack.com/archives/C03MSG8B7/p1596130335279500

https://gitlab.slack.com/archives/C0GQHHPGW/p1596131148111500

From @hollyreynolds

Hello! Does anyone know why some of these items have a green background? We thought maybe they were “new”, but not all items with the same creation/opened time have that style.

From @vitallium:

we highlight issues created today and we take the creation date in UTC but the display date is in your time zone.

From @smcgivern:

yeah, that's a weird system even if your timezone is UTC (mine is pretty close), because you'll have more green issues at the end of the day than the start 🤔

and something created just before UTC midnight will basically never show green

Proposal

We should see if users find the green background useful, or if there's another way we should be highlighting recently created issues (if at all).

This feature has been present in GitLab for years but I'm not sure specifically when or why it was added. @dzaporozhets do you have any other information on this?

MVC

• Use previous 24 hours relative to a user's given timezone.
• Remove the extra logic for checking new = < n previous hours + unedited so it would basically new = n previous hours

UX Follow up:

• Gather insights and feedback about the green background.
• It could also be worth combining this discovery with similar needs such as -- should an issue have a different colored background or visual indicator if you have a todo on it or if there is new activity on it from the last time that you viewed it?