Slider: Revision page slider does not support touch interactions on mobile devices

[yogeshbhutkar]

The slider on the revisions page lacks touch interaction support on mobile devices, making it difficult for users to navigate revisions using touch gestures. This limitation affects the feature's usability and accessibility on touchscreen devices.

To replicate, perform the following steps:

1. Create a post and ensure it has at least five revisions.
2. Open the revisions page.
3. On a mobile device, attempt to drag the slider.
4. Verify that the slider does not respond to touch gestures.

[yogeshbhutkar]

A screencast of the bug described above is attached here:

### Description

Trac ticket: https://core.trac.wordpress.org/ticket/63208

This PR adds touch event support, allowing users to drag the slider using touch gestures on mobile devices.

### Screencast

Before	After

[SirLouen]

Combined Reproduction and Patch Testing Report

Description

This report validates that this issue can be reproduced and the patch work as expected

Environment

• WordPress: 6.9-alpha-60093-src
• PHP: 8.2.28
• Server: nginx/1.27.4
• Database: mysqli (Server: 8.0.41 / Client: mysqlnd 8.2.28)
• Browser: Chrome 134.0.0.0 (Mobile)
• OS: Android
• Theme: Twenty Twenty-Five 1.1
• MU Plugins: None activated
• Plugins:
  • Test Reports 1.2.0

Reproduction Steps

This can be done from a browser in a responsive view, but I've tested using a phone.

1. Create a Post
2. Add multiple edits in the post and save, repeat this 2 or 3 times
3. Navigate to Revisions
4. Try to drag the revisions' slider.
5. 🐞 Slider doesn't move. You can still press on the checkpoints to switch revisions.

Expected Results

• The slider moves on drag

Actual Results after patch

• ✅ Issue resolved with patch.

[joedolson]

So, I certainly like the idea of making this change - but this does require an edit to a vendor library. If you look at jQuery UI on Github, this is clearly not a heavily maintained package, but editing a 3rd party library is something we need to think about cautiously.

I think we should probably instead try to push on getting ​https://github.com/jquery/jquery-ui/pull/2362 merged, if we think there might be a possibility of an update from the 3rd party.

I'm commenting on the jQuery UI issue to see if we can get any movement there.

[joedolson]

So, the official stance of the jQuery UI is that they are in maintenance mode: ​https://blog.jqueryui.com/2021/10/jquery-maintainers-update-and-transition-jquery-ui-as-part-of-overall-modernization-efforts/

Practically speaking, I think that means our only option is to modify our copy if we want to make any changes.

I think this becomes a larger discussion, for that reason; effectively, the entirety of jQuery UI is in maintenance mode, so this should be an "all or nothing" decision. Either we fork it, or transition away.

We are effectively transitioning away, in the new editor environment, but the tail of use for this will be very, very long.

The slider is currently used by the admin in classic widgets, revisions, and the Iris color picker.

[joedolson]

Per a comment from a jQuery UI committer, this is something they'll consider for a release; pending some linting fixes and the release of jQuery 4.0 RC 1. Given our time frame for WP 6.9, it may be that we'll be able to just update the version.

[nikunj8866]

@joedolson I've resolved the reported linting errors, so we should be good on that front.

[joedolson]

It's very unlikely that the jQuery UI release will be within the timeframe needed for 6.9, so I'm moving this to 7.0.