[11.x] Update to jQuery 4.0.x beta

https://blog.jquery.com/2024/02/06/jquery-4-0-0-beta/

Downloaded and copied the following files over the existing equivalents. They aren't actually linked on the download page, so lucky the URLs are predictable, at least once I realised it wasn't beta1.

https://code.jquery.com/jquery-4.0.0-beta.min.js
https://code.jquery.com/jquery-4.0.0-beta.js
https://code.jquery.com/jquery-4.0.0-beta.min.map

Updated core.libraries.yml

Did nothing else, I might be missing an obvious step, we'll find out.

I didn't add the jquery-migrate plugin because the update instructions seem confident that projects that have already updated to 3.5.0 or higher (we're on 3.7) won't need it and we should find out whether that's true for core or not.

We'll need figure out whether we'd want to add the migrate plugin for contrib/custom or not, whether in the core library or via an extra jquery_migrate module in core or contrib.

If this passes automated tests, we should tag this for manual testing and try to test some js-heavy UIs - ckeditor5 with the media library, menu or taxonomy drag and drop, views, layout builder, contextual links etc.

If those all work, then I think we should run the beta in 11.x HEAD (requires branching 10.3.x) so we've got the greatest chance of hitting any edge cases and to make it easier for contrib to start testing. We could even do that without resolving the migrate plugin question initially.

Real fails on

https://git.drupalcode.org/project/drupal/-/jobs/765398

https://git.drupalcode.org/project/drupal/-/jobs/765399

https://git.drupalcode.org/project/drupal/-/jobs/765412

e.g.

TypeError: $.isArray is not a function
    at states.Dependent.verifyConstraints
(http://localhost/subdirectory/core/misc/states.js?v=11.0-dev:307:13)

This should give us something to work with :)

I think we should split each error, or type of error, off to its own issue, they should all be committable to 10.3, then we can just keep rebasing/rerunning here until green unless we hit something bad.

Opened #3419730: [jQuery 4] TypeError: $.isArray is not a function at states.Dependent.verifyConstraints which seems hopefully trivial even to my non-JavaScript brain.

Also opened #3419734: [jQuery 4] jquery-form is unmaintained and not jQuery 4 compatible, fork it into core which is not going to be as trivial because it's in a library. edit, postponed that on #3189416: [PP-1] Remove jQuery Form dependency from misc/ajax.js which we should try to get done and is responsible for 99% of the test failures.

Combining #3420499: [jQuery 4] position.js uses deprecated function $.isWindow() and #3419734: [jQuery 4] jquery-form is unmaintained and not jQuery 4 compatible, fork it into core with the update from here, all tests are green except nightwatch: https://git.drupalcode.org/project/drupal/-/pipelines/91662

#3419734: [jQuery 4] jquery-form is unmaintained and not jQuery 4 compatible, fork it into core gives us a green test run for functional javascript, but it looks like there's still some nightwatch failures too, haven't looked those at all yet.

Edit: opened #3420713: Nightwatch tests fail with "unsupported pseudo: tabbable" after jQuery 4 update.

#3296098: Removal :tabbable usage in dialog.js might be the nightwatch failure.

#3296098: Removal :tabbable usage in dialog.js is the remaining blocker here.

Rebased the original branch here but getting unexplained CSS linting errors. So I redid the jQuery update steps posted above (not my original manual ones) in a new branch just in case it was a problem with the rebase.

The new MR is passing, not sure what the difference is since the diff is the same.

I had to remove the dialog :tabbable shim integration test, the deprecation message is no longer fired, presumably this is because we updated dialog in the blocking issue and now with jQuery 4 that code isn't executed. Maybe someone else understands that test better than me and I've got it wrong, but also we've now unblocked #3278625: Deprecate/remove jquery.tabbable.shim so should just go ahead there. There's still coverage, just not via dialog any more.

Looking at the performance test failures, but also it looks like #3420713: Nightwatch tests fail with "unsupported pseudo: tabbable" after jQuery 4 update is still a problem so unpostponed that one.

@finnsky we still have:

tabbable.jquery.shim:
  version: VERSION
  js:
    misc/jquery.tabbable.shim.js: {}
  dependencies:
    - core/drupal
    - core/tabbable
    - core/jquery

in core - isn't it the test coverage for that?

#3278625: Deprecate/remove jquery.tabbable.shim has been open for a long time, but was blocked on #3296098: Removal :tabbable usage in dialog.js.

I personally think to enable jQuery 4 testing for contrib, we should indeed remove the nightwatch coverage and sort out anything else later - it could mean going ahead and deprecating the tabbable shim in 10.3.0 for removal in 11.x and removing it from 11.x anyway. But would be good to get thoughts from FEFMs whether that's an acceptable approach.

I might do that to get a green MR here since the diff is pretty small. Any other approach we'll be blocked again here anyway, so it won't exactly hold it up.

@finnsky is right, we need to do it a 10.3 deprecation, I think but MR up on #3278625: Deprecate/remove jquery.tabbable.shim now.

I will include the 11.x commits from #3278625: Deprecate/remove jquery.tabbable.shim because it is just removals and it will allow us to get to a green test run here (hopefully).

Re #33 yeah I didn't the first time because I didn't know it existed, but now I do (and it's very nice).

#3278625: Deprecate/remove jquery.tabbable.shim is RTBC and tests are green here (with those changes applied).

Rebase looks good, thanks for lowering the budgets!