Per-thread overrides

Moderators who hold the Override thread split settings permission see a Thread Split entry in the thread tools menu. The form lets them change threshold, split mode, watcher migration, viewer notifications, and templates for that thread alone.

Every field is nullable. A null field means defer to the forum override (or the global option) for that setting; an explicit value means override.

Resolution order

Settings resolve in this order, picking the first non-null value:

thread override → forum override → global option

Manual split vs override

Action	Permission	Effect
Manually split a thread	Manually split a thread	Splits the thread now, ignoring threshold and grace-period configuration.
Override thread split settings	Override thread split settings	Changes how future auto-splits behave for this thread. Does not split now.

Use the override to dial a thread's behaviour; use the manual split to force one immediately.

Detaching a part from a chain

Moderators with Detach a thread from its chain see a Detach from chain action in the thread tools. Detaching removes the part from xf_mc_threadsplit_chain_thread; the thread becomes an ordinary standalone thread and the chain continues without it. Existing watchers and posts are untouched.

When per-thread overrides are useful

• A specific megathread that should never auto-split, even though its forum has thresholds enabled.
• A live event thread that should split on a smaller threshold than the rest of the forum.
• A long-running staff-only thread that needs a custom continuation template.