This PR is effectively taking the diff between
sg/master-stack commit: b6b5b1f
9.x.x/release commit: 808d18e
and applying it to master.

Edit (seb): Cheery-pick commit up to a2f64bb

Please read

PR workflow guidelines

• SRP ABV will start automatically on Yamato when you open your PR
• Changes to docs and md files will not trigger ABV jobs
• Consider making use of draft PRs if you are not 100% sure that your PR is ready for review
• ABV will restart if you add a new commit to a branch with an open PR (hence why you should consider using draft PRs)
• Adding [skip ci] (case insensitive) to the title of PRs will stop any jobs being trigger automatically - you will need to open Yamato and find your branch to run ABV
• You can also add [skip ci] to commit messages to prevent CI from running on that push
• Add [cancel old ci] to your commit message if you've made changes you want to test and no longer need the previous jobs

Checklist for PR maker

• Have you added a backport label (if needed)? For example, the need-backport-* label. After you backport the PR, the label changes to backported-*.
• Have you updated the changelog? Each package has a CHANGELOG.md file.
• Have you updated or added the documentation for your PR? When you add a new feature, change a property name, or change the behavior of a feature, it's best practice to include related documentation changes in the same PR.
• Have you added a graphic test for your PR (if needed)? When you add a new feature, or discover a bug that tests don't cover, please add a graphic test.

Purpose of this PR

Why is this PR needed, what hard problem is it solving/fixing?

Testing status

Manual Tests: What did you do?

• Opened test project + Run graphic tests locally
• Built a player
• Checked new UI names with UX convention
• Tested UI multi-edition + Undo/Redo + Prefab overrides + Alignment in Preset
• C# and shader warnings (supress shader cache to see them)
• Checked new resources path for the reloader (in developer mode, you have a button at end of resources that check the paths)
• Other:

Automated Tests: What did you setup? (Add a screenshot or the reference image of the test please)

Yamato: (Select your branch):
https://yamato.prd.cds.internal.unity3d.com/jobs/902-Graphics

Any test projects to go with this to help reviewers?

Comments to reviewers

Notes for the reviewers you have assigned.