Two findings, both from watching the bar refuse to change.
The Icon widget copies the desktop entry into the user's home and uses
the copy. A classroom that had already run kept the old icon and the old
command for ever: the package no longer contained a bell and the bar kept
showing one. The button is a task manager holding a single launcher now,
which resolves /usr/share/applications live — the place an OTA update
writes to — and costs nothing, because the classroom already runs one for
the applications.
NoDisplay=true then hid the entry from the very index that resolves
launchers, and the bar drew a blank page. There is no application menu in
this classroom for the entry to clutter, so it is indexable now.
Co-Authored-By: Claude Opus 5 <[email protected]>
The whole appliance UI is now configuration for a desktop Debian already
ships: a Plasma 6.3 session with a colour scheme, a look and feel package
that builds the bar, window rules, and KDE's own Kiosk restrictions.
Two things were measured rather than assumed, and both changed a decision.
Plasma restarts a crashed panel three times a minute and then gives up,
which is the failure a classroom has already had. Four lines of systemd
drop-in make it unconditional; the panel then survived eight SIGKILLs a
second apart, back each time in 2.4s.
Plasma draws a minimised task and a background task identically, so the
five states the room needs cannot all be shown. Rather than write a task
manager, the classroom removes minimise: clicking a launcher always means
show me this.
Co-Authored-By: Claude Opus 5 <[email protected]>
