diff --git a/src/ita/_layout.py b/src/ita/_layout.py
index 9a05492..2953c86 100644
--- a/src/ita/_layout.py
+++ b/src/ita/_layout.py
@@ -2,6 +2,7 @@
 """Layout commands: window group."""
 import asyncio
 import json
+import os
 import click
 import iterm2
 from ._core import cli, run_iterm, confirm_or_skip, next_free_name, capture_focus, restore_focus
@@ -26,7 +27,10 @@ def window_new(window_name, profile, background):
 	"""Create new window. Returns window ID.
 
 	CONTRACT §2 "Mandatory naming on creation (#342)" — when `--name` is
-	absent, the window is titled with the lowest free `w<N>` counter."""
+	absent, the window is titled with the lowest free `w<N>` counter.
+	#379: ITA_DEFAULT_BACKGROUND=1 env var is honored as a fallback default."""
+	if not background and os.environ.get('ITA_DEFAULT_BACKGROUND') == '1':
+		background = True
 	async def _run(connection):
 		app = await iterm2.async_get_app(connection)
 		captured = await capture_focus(app) if background else None
diff --git a/src/ita/_session.py b/src/ita/_session.py
index 8c63807..8413b5b 100644
--- a/src/ita/_session.py
+++ b/src/ita/_session.py
@@ -1,5 +1,6 @@
 # src/_session.py
 """Session lifecycle commands: new, close, activate, name, restart, resize, clear, capture."""
+import os
 from pathlib import Path
 import shlex
 import click
@@ -73,6 +74,10 @@ async def _session_records(connection):
 @click.option('--background', is_flag=True,
 	help='Create without shifting focus; restore previously-focused target after creation (#346).')
 def new(new_window, profile, session_name, reuse, replace, cwd, run_cmd, as_json, wait_reqs, no_wait, background):
+	# #379: honor ITA_DEFAULT_BACKGROUND=1 as a fallback default so tests
+	# (and agents) don't need to pass --background on every creation.
+	if not background and os.environ.get('ITA_DEFAULT_BACKGROUND') == '1':
+		background = True
 	"""Create new tab (or window). Returns name (stdout) and session ID.
 
 	By default waits until the session is alive and writable before returning
diff --git a/src/ita/_tab.py b/src/ita/_tab.py
index 831cc63..71d573b 100644
--- a/src/ita/_tab.py
+++ b/src/ita/_tab.py
@@ -2,6 +2,7 @@
 """Tab commands: new, close, activate, navigate, list, info, detach, move, profile, title."""
 import asyncio
 import json
+import os
 import click
 import iterm2
 from ._core import cli, run_iterm, next_free_name, _fresh_name, capture_focus, restore_focus
@@ -29,6 +30,9 @@ def tab_new(window_id, tab_name, profile, background):
 	is required; there is no implicit 'current window' fallback.
 	CONTRACT §2 "Mandatory naming on creation (#342)" — when `--name` is
 	absent, the tab is titled with the lowest free `t<N>` counter."""
+	# #379: env-var fallback so fixtures can opt into background suite-wide.
+	if not background and os.environ.get('ITA_DEFAULT_BACKGROUND') == '1':
+		background = True
 	if not window_id:
 		raise ItaError("bad-args",
 			"no window specified. Use --window NAME or --window UUID-PREFIX. "
diff --git a/tests/conftest.py b/tests/conftest.py
index 170f647..372ec00 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -10,8 +10,29 @@
 Layers L3 + L4 added here as the catastrophic-leak circuit breaker.
 """
 import atexit
+import os
 import pytest
 
+# #379: fixtures create sessions/tabs/windows in the background by default
+# so test runs don't steal focus from the human at the keyboard. Opt-out
+# in a specific test with monkeypatch.delenv('ITA_DEFAULT_BACKGROUND', False).
+os.environ.setdefault('ITA_DEFAULT_BACKGROUND', '1')
+
+# #384: suppress the "Last login: <date> on ttys###" banner macOS prints
+# when a new login shell starts. The banner scrolls every test-created
+# session by two lines, which pushes prompts out of sight during capture
+# assertions. Touching ~/.hushlogin is the Unix-standard way to silence
+# it; zero-byte file, idempotent, creates only if missing.
+try:
+	from pathlib import Path as _Path
+	_hush = _Path.home() / '.hushlogin'
+	if not _hush.exists():
+		_hush.touch()
+except Exception:
+	# Best-effort: a read-only home or weird permissions shouldn't break
+	# the test run. Banner is cosmetic, not correctness.
+	pass
+
 from helpers import (  # noqa: F401
 	ITA, ita, ita_ok, _extract_sid, _all_session_ids,
 	_open_test_sessions, _close_test_sessions,
@@ -53,6 +74,12 @@ def _atexit_close_test_sessions():
 
 LEAK_CEILING = 50
 
+# #383: mid-suite leak audit. Snapshots ita-test-* session count at the
+# start of each test, compares in teardown, logs delta to stderr when it
+# looks suspicious. Non-fatal (the L4 hard-ceiling handles that) — purpose
+# is locating *which* test leaks when cumulative counts drift upward.
+_LEAK_SNAPSHOT: dict[str, int] = {}
+
 
 def _count_test_sessions() -> int:
 	try:
@@ -68,6 +95,15 @@ def _count_orphan_windows() -> int:
 		return 0
 
 
+def pytest_runtest_setup(item):
+	"""#383: snapshot session/window count before the test runs, so the
+	teardown hook can compute a delta. Skipped on the contract fast-lane
+	(same rationale as the teardown hook — those tests don't touch iTerm2)."""
+	if 'contract' in item.keywords and 'integration' not in item.keywords:
+		return
+	_LEAK_SNAPSHOT[item.nodeid] = _count_test_sessions()
+
+
 def pytest_runtest_teardown(item, nextitem):
 	"""After every test, check the leak ceiling on BOTH ita-test-* sessions
 	AND orphan default windows (#348). Hard-abort if either exceeded —
@@ -82,6 +118,17 @@ def pytest_runtest_teardown(item, nextitem):
 		return
 	sess_count = _count_test_sessions()
 	win_count = _count_orphan_windows()
+	# #383: mid-suite leak audit. Log (non-fatally) when a test leaves more
+	# ita-test-* sessions than it started with — the teardown finalizers
+	# ran, so any delta means a fixture teardown missed something.
+	before = _LEAK_SNAPSHOT.pop(item.nodeid, None)
+	if before is not None and sess_count > before:
+		import sys
+		print(
+			f"\n[leak-audit #383] {item.nodeid}: "
+			f"ita-test-* sessions {before} -> {sess_count} (+{sess_count - before})",
+			file=sys.stderr,
+		)
 	if sess_count > LEAK_CEILING or win_count > LEAK_CEILING:
 		try:
 			_close_test_sessions(_open_test_sessions())
@@ -115,7 +162,9 @@ def session(request):
 	closes that window in teardown too (otherwise iTerm2 leaves an orphan
 	default-shell window behind when our session is closed).
 	"""
-	safe_name = (TEST_SESSION_PREFIX + request.node.name[:30]).replace(' ', '_')
+	# #380: use the full test node name (with parametrize bracket spec)
+	# so every ita-test-* object is legible in iTerm2's session list.
+	safe_name = (TEST_SESSION_PREFIX + request.node.name).replace(' ', '_')
 	windows_before = _all_window_ids()
 	r = ita('new', '--name', safe_name)
 	assert r.returncode == 0, f"Failed to create session: {r.stderr}"
@@ -137,7 +186,8 @@ def shared_session(request):
 	"""Module-scoped session for read-only tests (faster than per-test).
 
 	#348: same window-tracking discipline as `session`."""
-	safe_name = (TEST_SESSION_PREFIX + 'shared-' + request.module.__name__[:20]).replace(' ', '_')
+	# #380: full module name for legibility.
+	safe_name = (TEST_SESSION_PREFIX + 'shared-' + request.module.__name__).replace(' ', '_')
 	windows_before = _all_window_ids()
 	r = ita('new', '--name', safe_name)
 	assert r.returncode == 0, f"Failed to create module session: {r.stderr}"
diff --git a/tests/fixtures/sessions.py b/tests/fixtures/sessions.py
index e55f405..0c77a3d 100644
--- a/tests/fixtures/sessions.py
+++ b/tests/fixtures/sessions.py
@@ -33,7 +33,8 @@ def _teardown():
 	request.addfinalizer(_teardown)
 
 	def create(n: int = 1) -> list[str]:
-		safe_base = (TEST_SESSION_PREFIX + request.node.name[:20]).replace(' ', '_')
+		# #380: full node name for legibility in iTerm2's session list.
+		safe_base = (TEST_SESSION_PREFIX + request.node.name).replace(' ', '_')
 		# TESTING.md §4.1 L2: register each successful sid into all_sids
 		# IMMEDIATELY (not after the batch). If create() raises mid-batch,
 		# the addfinalizer still cleans up everything we managed to spin up.
@@ -98,8 +99,9 @@ def shell(request):
 	Fish is skipped automatically when ``shutil.which("fish")`` returns None.
 	"""
 	shell_name: str = request.param
+	# #380: full node name for legibility in iTerm2's session list.
 	safe_name = (
-		TEST_SESSION_PREFIX + "shell-" + shell_name + "-" + request.node.name[:15]
+		TEST_SESSION_PREFIX + "shell-" + shell_name + "-" + request.node.name
 	).replace(" ", "_")
 
 	r = ita("new", "--name", safe_name, "--run", f"exec {shell_name}\n")