Update project page with new branch details

I think it would be nice if the suggested steps for updating from Facets 2 to 3 were listed, since I wasn't sure how much updating to version 3 would change, and what a recommended method could be ... Perhaps add something along these lines? (Feel free to re-write)

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Facets 2

Facets 2 works with Drupal Core Search and Search API.
It is kept available for existing projects using Facets 2 + Ajax as there is no upgrade path for this setup. Updating from 2 to 3 without AJAX support is possible.

Updating from Facets 2 to 3

You can update from Facets version 2 to 3, and everything stays the same, except for no AJAX support for "Facet blocks". These are the suggested update steps:

1. Update to Facets 3
2. Rebuild, using View Filters, and not the classic method via the Facet UI
3. Delete old Facet UI filters, and their individual blocks

The intro text ("You can update from Facets ...") is not quite right .... I just tried to update Facets 3, and some crucial features are not quite ready, unless you have very few Facets, and you are all right with the default placement above the form. If you want to place a Facet somewhere else, you need to use https://www.drupal.org/project/configurable_views_filter_block/ → but AJAX doesn't work ...

You can update from Facets version 2 to 3 with these steps. Note that most things work, but some features are not possible, like placing Facets somewhere else than above the form in Views (the standard) and have AJAX support, since you need to use https://www.drupal.org/project/configurable_views_filter_block/ → which does not yet support AJAX:

The issues for AJAX support (Configurable Views Filter Block issue, and the needed Drupal core issue):

• 💬 Works with AJAX enabled? Active
• 🐛 Views hardcodes exposed filter block form ID's which breaks AJAX when the same form is shown multiple times on one page Needs work

There are also these tasks, which are in the making for Configurable Views Filter Block:

• 🐛 Hidden filters in a collapsible details element still display the summary Active
• ✨ Provide block ID as context in form so form_alter hooks can tell which block's form they have Active
• ✨ Add option to remove (instead of hide) unnecessary filters Active

I think it would be nice to alert potential Facets 2 to 3 updaters that some features are not yet ready, to prevent them from wasting time needlessly ... I spent quite some time re-building a solution, only to hit dead ends.

Priority for the Drupal core issue 🐛 Views hardcodes exposed filter block form ID's which breaks AJAX when the same form is shown multiple times on one page Needs work required to fix 💬 Works with AJAX enabled? Active was just elevated to Major, so hopefully it can be fixed soonish ...