WordPress 6.8 Compatibility

WordPress 6.8 is set to release on *April 15, 2025*.

- Planning: [make.wordpress.org/core/6-8](https://make.wordpress.org/core/6-8/)

Let's use this issue to keep track of anything that may come up until then.

- [x] Update our tested up to: https://github.com/Automattic/vulcan/issues/745
- [ ] https://github.com/Automattic/jetpack/issues/40040
- [x] https://github.com/Automattic/jetpack/issues/42507
- [x] https://github.com/Automattic/jetpack/issues/42395
- [x] https://github.com/Automattic/jetpack/issues/42421
- [x] https://github.com/Automattic/jetpack/issues/42579
- [x] https://github.com/Automattic/jetpack/issues/42577 and https://github.com/Automattic/jetpack/issues/42575

And **in the next plugin release* , to give folks time to update:

- [x] https://github.com/Automattic/jetpack/pull/43192
- [x] https://github.com/Automattic/jetpack/pull/43246

Once WordPress 6.7 is the minimum required version in Jetpack, we can consider implementing the following changes:

- [x] https://github.com/Automattic/jetpack/issues/39921
- [x] https://github.com/Automattic/jetpack/issues/39922
- [x] https://github.com/Automattic/jetpack/issues/39924
- [ ] https://github.com/Automattic/jetpack/issues/39853

In addition to the above, we can follow the dev-notes that will drop here about the release:
[make.wordpress.org/core/tag/dev-notes+6-8](https://make.wordpress.org/core/tag/dev-notes+6-8)

We can also follow the source of truth: **TBD*

-------

For reference: prior art for WordPress 6.7 compat: #38902

Start by reviewing the linked Jetpack issues and pull requests, especially #40040, #42507, #42395, #42421, #42579, #42577, #42575, #43192, and #43246. Read the WordPress 6.8 planning page and dev notes, then identify any remaining compatibility work. Done means all applicable checklist items are resolved and Jetpack supports the WordPress 6.8 release.

Written by the indexing model from the issue text.