"What's New" screen confusing for minor updates

[scribu]

As ​reported on WPTavern, when you ugprade to 3.3.1, the "What's New" screen makes it seem like all the new features were introduced in 3.3.1 and not 3.3.

We should add a header below the short summary to the effect of "New features introduced in 3.3".

This was widely discussed on tickets and in IRC. It was decided that a maintenance/security release was just another "feature" and should have similar styling. I can see how it can be confusing, and there were some arguments made that an in-branch update should behave differently than an update that crosses a major version, but nothing came of it.

Replying to nacin:

...an in-branch update should behave differently than an update that crosses a major version, but nothing came of it.

Yes, this exactly. My recommendation would be only to show the "Welcome" screen when the version change is major - i.e. 3.2.x to 3.3.x. Presumably, an install undergoing a version change from 3.3.x to 3.3.y would already have shown the "Welcome" screen upon update to 3.3.x, so there would be no need to show it again.

As a compromise, perhaps add a one-time admin notice upon minor-version update, with a note/link directing the user to the "Welcome" screen in order to see the version changes.

At the same time, regardless of the eventual approach taken, adding the minor-version changes/updates to the "Welcome" screen would still be useful/beneficial, since the screen still exists even if not displayed by default upon update.

As we're trying to de-emphasize the importance of point release updates (not as in "you don't need to update" but rather "no big deal" and "might as well be automatic") we should probably not redirect to the welcome screen the same way we do for a major release.

Possibly related: #19762