Remove bbb control panel adapters

[esteele]

I think some of these can be removed now that the portal_properties entries are all moved into the regisry

[tisto]

Wouldn't it make sense to keep those until 5.1? @davisagli specifically asked me to implement those adapters to keep backwards compatibility.

[jensens]

There's not one line documentation in the bbb folder on how they are supposed to be used. Can you @tisto or @davisagli explain briefly?

[tisto]

@jensens just have a look at one of the tests :)

https://github.com/plone/Products.CMFPlone/blob/master/Products/CMFPlone/controlpanel/tests/test_controlpanel_bbb_editing_adapter.py

[jensens]

Still relevant for Plone 6. The bbb/ directory with legacy backward-compatibility control panel adapters still exists. Milestoned to 6.1.

[jensens]

Current state analysis (2026-03-30)

The BBB adapters in controlpanel/bbb/ are still used in production code — they're not just backwards compatibility anymore:

Direct getAdapter() callers (easy to fix)

• plone.restapi services/users/add.py (lines 72, 230) and services/users/update.py (line 83): getAdapter(portal, ISecuritySchema) — can be replaced with registry.forInterface(ISecuritySchema, prefix="plone")
• Products.CMFPlone controlpanel/browser/usergroups.py (lines 59, 63): getAdapter(context, IUserGroupsSettingsSchema) — same fix

Implicit usage (harder)

• z3c.form's AttributeField data manager calls self.field.interface(context) which triggers ZCA adapter lookup. All RegistryEditForm-based control panels rely on this. Needs a solution before full removal.

Proposed plan

1. ✅ Deprecate BBB controlpanel adapter. #3735 — add deprecation warnings (ready to land)
2. 🔧 Fix getAdapter callers in plone.restapi and CMFPlone to use registry.forInterface() directly (PRs in progress)
3. 🔬 Investigate z3c.form data manager adaptation — either fix in z3c.form or provide an alternative adapter registration mechanism
4. 🗑️ Remove controlpanel/bbb/ once all callers are migrated

Closing #3734 (the removal PR) in favor of this incremental approach.