docs/oss/configuration/configuration-deprecated.md
This document lists configuration options that have been deprecated or removed from React on Rails.
For current configuration options, see Configuration.
Status: ⚠️ REMOVED in v16.6.0
This configuration option has been removed. React on Rails Pro now performs early hydration automatically for streamed components; there is no per-component toggle. Non-Pro users are not affected.
Migration: Remove any config.immediate_hydration lines from your configuration and any immediate_hydration: keys passed to react_component / stream_react_component — both are no-ops and can be safely deleted.
See CHANGELOG.md for details.
Status: ⚠️ REMOVED in v17.0.0
Deprecated in v16 and removed in v17. Setting config.defer_generated_component_packs now raises NoMethodError at boot. Use config.generated_component_packs_loading_strategy instead.
Migration:
# Old (removed):
config.defer_generated_component_packs = true # → :defer
config.defer_generated_component_packs = false # → delete the line (was a no-op)
# New:
config.generated_component_packs_loading_strategy = :defer # or :sync
The old option was truthy-gated: only = true had any effect (it set :defer). = false was a no-op that fell through to the default strategy — it did not mean :sync. So migrate = true to :defer, and simply delete = false. Set :sync explicitly only if you specifically relied on synchronous (blocking) pack loading.
If you delete the line without setting generated_component_packs_loading_strategy, the default strategy applies: :async for Pro or :defer for non-Pro on Shakapacker 8.2.0+, and :sync on older Shakapacker.
See CHANGELOG.md for more details.
Status: ⚠️ REMOVED in v17.0.0
Deprecated in v16 and removed in v17. Setting config.generated_assets_dirs now raises NoMethodError at boot. Delete the line — public asset paths are determined automatically from public_output_path in config/shakapacker.yml.
Status: ⚠️ REMOVED in v17.0.0
Deprecated in v16 and removed in v17. Setting config.skip_display_none now raises NoMethodError at boot. Delete the line — it had no runtime effect.