test: rehearse the stable rooms' upgrade on every canary, and list Sunday's checks

update_canary.sh now also validates the exact package it is about to
publish as an upgrade from whatever stable names — 0.2.2 today, several
releases behind the laptop's canary. A package that upgrades the laptop
and breaks the desktops has to fail before it is published.

The lab print check runs in the Plasma lab as well as a plain container:
its rig lived in /tmp, which is a tmpfs there that docker cp cannot write
into, and its inline-PDF server shared a port with another test server.

docs/testing.md has the physical checks for 0.2.6.1 — paper through
Elmer, the real keyboard's zoom keys, the machine's graphics through
--diagnose, sign-out with a real account — before stable moves.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

docs/testing.md

@@ -574,3 +574,90 @@ ifupdown stanza is already gone. **Do not run `--adopt` on it.**
 - [ ] `nmcli -g 802-11-wireless.hidden connection show "ROGC Classroom"`
       still reports `yes`
 - [ ] The laptop still reconnects after a reboot
+
+## Wonder Ink — 0.2.6.1, before it goes to stable
+
+Everything below was done in the lab except what a lab cannot do: paper,
+a classroom's own graphics, a real keyboard, its network and its screen.
+Those are these checks. Stable stays on 0.2.2 until they pass.
+
+Before starting, on each machine: `dpkg-query -W ekklesia-classroom`
+must say `0.2.6.1`. The desktops only get it once stable is moved, so on
+a desktop install it by hand for the test:
+
+```
+curl -fsSL -o c.deb https://updates.riverofglorymn.org/canary/latest.deb
+sha256sum c.deb     # must match .../canary/manifest.json
+sudo apt-get install -y ./c.deb && sudo reboot
+```
+
+This does **not** move the machine to canary (see provisioning.md): its
+next automatic update follows stable again, which is still 0.2.2 — so
+after testing, either promote or reinstall 0.2.2 the same way.
+
+### Little Waders — printing through Elmer
+
+- [ ] Open Wonder Ink, sign in, open a lesson with a worksheet
+- [ ] Click the worksheet; it opens as a tab named after the file, with a
+      document icon
+- [ ] Ctrl+P (or right-click → Print…): the preview shows the worksheet's
+      own pages, page count right, ‹ › turn them
+- [ ] Printer shows **Elmer**, preselected
+- [ ] Print → a notification "Sent to the printer — … — Elmer", Wonder Ink
+      stays open on the lesson
+- [ ] **The worksheet comes out of Elmer**, every page, right size, in colour
+- [ ] Pages `2`, Copies `2`, Black and white → exactly two grey copies of
+      page 2 come out
+- [ ] Print a normal lesson page the same way; it comes out, Letter
+- [ ] Open the preview and press Cancel → nothing prints
+- [ ] Print three times in a row → three printouts, no crash
+- [ ] `lpstat -W completed -o` shows each job; `journalctl --user -b | grep
+      "printed '"` shows Wonder Ink's line for each
+
+### Size and zoom
+
+- [ ] A lesson in Wonder Ink is the same size as the same page in the
+      browser on that machine (it was smaller in 0.2.2)
+- [ ] **Ctrl and +** (the real keyboard), **Ctrl and −**, **Ctrl and 0**
+      change it; a "Lesson size" badge appears
+- [ ] Open a second tab: it is the same size; the − 100% + and Print
+      buttons are at the top right
+- [ ] Close Wonder Ink and open it again: the size is remembered
+- [ ] A worksheet tab's own − / + (in the PDF toolbar) zoom it
+- [ ] A lesson video still goes fullscreen and comes back with the tabs
+
+### Loading, and the machine's graphics
+
+From the maintenance terminal (Meta+Ctrl+Alt+Shift+K), in the session:
+
+```
+classroom-wonderink --diagnose
+```
+
+- [ ] Note the **GPU line**. A driver's name is right. "none … drawing in
+      software" means QtWebEngine has no GPU on this machine — compare
+      `chrome://gpu` in the browser; if Chrome has one, that is the cause of
+      slow lessons and is the next thing to fix
+- [ ] Note the sign-in time (the lab: about 2.9 s wired). Much slower here
+      with a driver named above points at the network
+- [ ] `free -m`: Wonder Ink needs about 610 MB plus 115 MB per extra tab
+
+### Signing out
+
+- [ ] Sign in, close Wonder Ink, open it again → **signed out**. (Cookies
+      are session-only and measured so; the site's Local Storage is not
+      cleared, which is the one way this could fail and has never been
+      tested with a real account)
+
+### After a reboot, and the other rooms
+
+- [ ] Reboot Little Waders: it comes up as the classroom, Wonder Ink opens
+- [ ] On one other desktop, 0.2.6.1 installed: the browser, the DVD player
+      where there is a drive, Parent Call where enabled, sound through the
+      television, the panel order — all as on 0.2.2
+- [ ] **Presentations is not on the panel** of any desktop
+      (`grep PRESENTATIONS_ENABLED /etc/ekklesia-classroom/device.conf`
+      says `false`)
+
+If anything here fails, leave the desktops on stable 0.2.2 and fix it in
+0.2.6.2 on canary.