The desktop failed to start in a browser that had cached noVNC 1.6
from the Debian desktop image: its vnc.html, which has no clipboard
Clear button, ran the Ubuntu image's 1.3 ui.js, which wires one up
and threw "Cannot read properties of null". websockify sends only
Last-Modified, so browsers cache noVNC on a guess, and it answers a
revalidation with 304 when the file on disk is older than the copy.
Serve noVNC through websockify-no-store, which adds Cache-Control:
no-store to every response, and from /novnc/ rather than /, so no
browser holds a stale copy at the paths the desktop now uses.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>