A monitor took the current DOM as its baseline on install, so a video that was
already present counted as "not a change" and was never announced. The discovery
poll added in the previous commit reinstalled monitors every 2s, which meant a
video appearing between two reinstalls was silently swallowed — the reported
debug log had no [Content] lines at all, which is the signature of exactly this.
Monitors now announce a video that is already there when they install, which
also makes the rebuilt-frame case work by construction rather than by timing.
The reinstall interval is raised to 5s now that each install is informative.
Also adds docs/frame-targeting-handoff.md: why v3.1.2 worked immediately with
webNavigation, why reconstructing that single call from sweeps, a learned
registry, per-frame monitors and a poll keeps producing timing windows, and the
proposed structural replacement (chrome.scripting.registerContentScripts with
allFrames, no new permission) together with the project invariant it conflicts
with — which is the owner's decision, not a code change to make unasked.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Timo