diff --git a/goodwe_controller/test_safety126.py b/goodwe_controller/test_safety126.py
index 03301f1..a76f152 100644
--- a/goodwe_controller/test_safety126.py
+++ b/goodwe_controller/test_safety126.py
@@ -22,6 +22,8 @@ quarter's edge as on the rig.
    before, and names both batteries.
 3. `misses_aim()` on its own.
 4. The page and the "Why" on a decision within the aim.
+
+Mutations (MUTATION.md, purged copies) are listed in the pull request.
 """
 
 import asyncio
@@ -39,6 +41,7 @@ sys.path.insert(0, HERE)
 sys.path.insert(0, os.path.join(HERE, "tools"))
 
 import opt11p3_replay as rp                                    # noqa: E402
+from named_absence import first, nth, present                  # noqa: E402
 import app.main as m                                           # noqa: E402
 import app.p1 as p1mod                                         # noqa: E402
 from app import homeview, messages, peakguard, tariff          # noqa: E402
@@ -335,8 +338,9 @@ for tag, onset, kw in (
     print(f"    notifications at {_th} s; with the fix reverted {_tb} s")
     check(f"{tag}: the first at the same cycle as before the fix "
           f"({first_h} s, {first_b} s), and none that was not raised before",
-          first_h is not None and first_h == first_b and _th
-          and _th[0] == _tb[0] and set(_th) <= set(_tb))
+          first_h is not None and first_h == first_b
+          and present(nth(_th, 0)) and nth(_th, 0) == nth(_tb, 0)
+          and set(_th) <= set(_tb))
     check(f"{tag}: the red peak row and its banner while it stands",
           any(s[4] for s in head["seen"]))
 
@@ -392,8 +396,10 @@ _dec = peakguard.PeakDecision(
 def page(d):
     """(the peak row is red, the "Why" says peak) for decision `d`."""
     _c.peak_guard, _c._peak_floor_limited = d, False
-    row = next(r for r in _c.checks(datetime.now(timezone.utc))
-               if r["id"] == "peak_guard")
+    row = first((r for r in _c.checks(datetime.now(timezone.utc))
+                 if r["id"] == "peak_guard"), "peak row")
+    if not present(row):
+        return {"red": None}, None
     return dict(row, red=row["ok"] is False and not row.get("warn")), \
         homeview.peak_engaged(_c)
 
@@ -402,7 +408,7 @@ _r1, _w1 = page(_dec)
 _r2, _w2 = page(dataclasses.replace(_dec, within_aim=True))
 check("a saturated decision: red 'Load too high' row and the 'Why' peak, "
       "as before", _r1["red"] and _w1)
-check("...within the aim: neither", not _r2["red"] and not _w2)
+check("...within the aim: neither", _r2["red"] is False and _w2 is False)
 _lim = dataclasses.replace(_dec, floor_w=0.0, saturated=False,
                          floor_limited=True, soc=10.0,
                          soc_floor_reason=peakguard.FLOOR_AT_SOC_FLOOR)
@@ -410,7 +416,8 @@ _r3, _w3 = page(_lim)
 _r4, _w4 = page(dataclasses.replace(_lim, within_aim=True))
 check("floor-limited at 0 W: the red reserve row with its banner, as "
       "before", _r3["red"] and "banner" in _r3 and not _w3)
-check("...within the aim: no red row", not _r4["red"] and not _w4)
+check("...within the aim: no red row",
+      _r4["red"] is False and _w4 is False)
 
 
 # ============================================================================ #