VERSION 1.3
Accuracy fixes, all found by instrumenting real jumps on a live cam
after the stream had a short outage.

• Jumps that crossed a gap in the stream could wrongly report
  "Stream was down then" for a moment that was really there, and land
  a few seconds early. They now land exactly.
• Times in the older part of the rewind buffer could be read as
  belonging to the wrong day and reported as unreachable. They now
  resolve correctly.
• A time that hasn't been broadcast yet now says so, instead of
  reporting a landing that didn't happen.
• Fixed a rare case where pause stopped responding after a reload.
• On a slow connection the held frame no longer lifts partway through
  a jump.
• L now waits until the picture is actually back before saying
  "Back to live", and lands on the live edge rather than a second or
  two behind it.

No new permissions, files, or network activity.

VERSION 1.2
Reduces the visual footprint of the UI while adding keyboard shortcuts (pause, back-to-live, ±5s nudge). Gulliver now holds the player paused during a jump for landing accuracy. Playback control uses the page player's own pauseVideo()/playVideo(), reached through the same MAIN-world script already used for seekTo()/seekToLiveHead().

No new permissions, files, or network activity.

v1.1 note: Simple change raising minimum Firefox version to 140 to match the APIs the extension uses.