diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7ece776..e0603c1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -111,12 +111,19 @@ jump, four new base packages and a new mailbox feature. The release carrying a
   are `*`, so a mismatch is silent at runtime) and that the atelier sidebar
   **paints**.
 
-  **User-visible behaviour change, deliberately not overridden.** 1.0.0 makes
-  the TUI fullscreen by default, replacing the terminal's normal scrollback;
-  `tuiMode: "regular"` restores the old behaviour. No baked default is set, so
-  the image inherits upstream's choice rather than silently pinning the fleet to
-  either one. If the fleet wants the old scrollback, that is a one-line settings
-  change, not a rebuild.
+  **User-visible behaviour change: the TUI is now fullscreen.** 1.0.0 changed the
+  default `tuiMode` to `"fullscreen"`, which draws into the terminal's alternate
+  screen — so the transcript no longer accumulates in the terminal's (or tmux's)
+  native scrollback. **Upstream's default is adopted deliberately**, not
+  inherited by omission: no `tuiMode` is baked, so the image follows pi rather
+  than pinning the fleet to either mode. The way back is documented in README
+  → *Terminal UI mode*: `"tuiMode": "regular"` in `~/.pi/agent/settings.json`
+  for every session, `pi --tui-mode regular` for one, or the same key in a
+  project's `.pi/settings.json` for one project. That section also covers the
+  four related `fullscreen*` settings — including `fullscreenWheelScrollLines`,
+  whose `"auto"` behaviour differs over SSH, which is how this container is
+  normally driven — and records that pi-atelier's sidebar works in both modes,
+  so reverting costs nothing.
 
 - **pi-atelier `v0.10.3` (`ed3837b`) → `v0.13.0` (`34d26f1`)** — closes the
   two-minor gap v1.9.5 named as the pi bump's residual risk. `peerDependencies`
diff --git a/DOCKER_HUB.md b/DOCKER_HUB.md
index 7c8f7ef..71043aa 100644
--- a/DOCKER_HUB.md
+++ b/DOCKER_HUB.md
@@ -56,6 +56,8 @@ Full setup guide — authentication for each provider (Anthropic, OpenAI, Gemini
 
 The entrypoint deploys/registers all of these on first container start. Re-running is idempotent and preserves user edits.
 
+**Terminal UI mode — fullscreen by default.** pi 1.0.0 made the TUI fullscreen, and this image adopts upstream's default. Fullscreen uses the terminal's alternate screen, so the transcript no longer lands in your terminal's (or tmux's) native scrollback. To get the previous behaviour back, set `"tuiMode": "regular"` in `~/.pi/agent/settings.json`, or pass `pi --tui-mode regular` for a single session. The bundled pi-atelier sidebar works in both modes. See the README for the related `fullscreenExitOutput` / `fullscreenScrollbar` / `fullscreenCopyOnSelect` / `fullscreenWheelScrollLines` settings — the last one behaves differently over SSH, which is how this container is usually driven.
+
 ### MemPalace (persistent agent memory)
 
 - **MemPalace** + MCP server — semantic search over conversation history, knowledge graph, diary; queryable via 29 `mempalace_*` tools inside pi
diff --git a/Dockerfile.variant b/Dockerfile.variant
index 2e120dc..161ead6 100644
--- a/Dockerfile.variant
+++ b/Dockerfile.variant
@@ -190,11 +190,13 @@ ARG USER_NAME=developer
 # (published 2026-10-01T19:15Z) and neither obsmem nor atelier has a commit
 # naming it. Acceptance must prove the obsmem workers CAP TURNS (peerDeps are
 # `*`, so a mismatch is silent) and that the atelier sidebar PAINTS.
-# USER-VISIBLE BEHAVIOUR CHANGE, deliberately NOT overridden here: 1.0.0 makes
-# the TUI fullscreen by default, which replaces the terminal's normal
-# scrollback. `tuiMode: "regular"` restores the old behaviour. No baked default
-# is set, so the image inherits upstream's choice rather than silently pinning
-# the fleet to either one.
+# USER-VISIBLE BEHAVIOUR CHANGE, decided rather than inherited: 1.0.0 makes the
+# TUI fullscreen by default, which replaces the terminal's normal scrollback.
+# Upstream's default is ADOPTED on purpose and no `tuiMode` is baked here, so
+# the image follows pi instead of pinning the fleet to either mode. The revert
+# is documented (README -> "Terminal UI mode"): `"tuiMode": "regular"` in
+# ~/.pi/agent/settings.json, `pi --tui-mode regular` for one session, or the
+# same key in a project's .pi/settings.json.
 ARG PI_VERSION=1.0.0
 ARG PI_TOOLKIT_REF=main
 ARG PI_EXTENSIONS_REF=main
diff --git a/README.md b/README.md
index 78d7ca6..5ca14d3 100644
--- a/README.md
+++ b/README.md
@@ -358,6 +358,61 @@ DOT syntax errors instead of crashing. Then in Studio: open the PNG (or a
 `.md` that embeds it) and hit **refresh-from-disk** after each edit.
 Note: SVG is **not** in Studio's local-image-link allowlist — use PNG.
 
+## Terminal UI mode: fullscreen is the default (since v1.10.0)
+
+pi **1.0.0** changed the default terminal UI mode to **fullscreen**, and this
+image adopts upstream's default rather than overriding it. Fullscreen draws into
+the terminal's alternate screen, so pi's transcript no longer accumulates in your
+terminal's native scrollback — you scroll inside pi instead, and on exit pi
+prints the transcript (`fullscreenExitOutput`).
+
+That is a real behaviour change if you were used to the old mode, so here is the
+way back. Nothing in the image is pinned, so all three routes below work:
+
+| Scope | How |
+|---|---|
+| **Permanently, for every session** | add `"tuiMode": "regular"` to `~/.pi/agent/settings.json` |
+| **One session** | `pi --tui-mode regular` |
+| **One project only** | add `"tuiMode": "regular"` to that project's `.pi/settings.json` — project settings override the agent directory |
+
+The settings file is plain JSON and `tuiMode` is top-level, so the minimal
+permanent change is:
+
+```bash
+# merge the key without disturbing the rest of the file (python3 is always present)
+python3 - <<'PY'
+import json, pathlib
+p = pathlib.Path.home() / ".pi/agent/settings.json"
+d = json.loads(p.read_text()) if p.exists() else {}
+d["tuiMode"] = "regular"        # "fullscreen" is pi's default
+p.write_text(json.dumps(d, indent=2) + "\n")
+PY
+```
+
+If you stay on fullscreen, four related settings are worth knowing — all
+documented in pi's own `docs/settings.md` under *Terminal and display*:
+
+- `fullscreenExitOutput` — `"transcript"` (default) or `"resume-hint"`: what pi
+  leaves behind in the terminal when fullscreen exits.
+- `fullscreenScrollbar` — `"auto"` (default), `"always"`, `"hidden"`.
+- `fullscreenCopyOnSelect` — `true` by default; selecting text copies it.
+- `fullscreenWheelScrollLines` — `"auto"` by default. Relevant **here** in
+  particular: this container is normally driven over SSH, and over SSH `"auto"`
+  accelerates fast wheel spins to at most 6 lines per event (local macOS
+  terminals accelerate on their own, so there it moves one line). `Alt`+wheel
+  moves five times as far.
+
+Two notes specific to this image:
+
+- **tmux.** Fullscreen uses the alternate screen, so `tmux` copy-mode scrollback
+  shows the pane's history *around* pi, not pi's transcript. Scroll within pi,
+  or use `"tuiMode": "regular"` if you rely on tmux copy-mode to search the
+  conversation.
+- **pi-atelier.** The bundled sidebar works in both modes — upstream has handled
+  regular and fullscreen renderers separately since pi 0.84, including
+  fullscreen divider dragging and keeping sidebar text out of fullscreen
+  selection — so switching back to `regular` does not cost you the sidebar.
+
 ## Using pi-atelier (TUI sidebar)
 
 `pi-atelier` is bundled in **both** variants (vendored at `/opt/pi-atelier`,