The fps line of the performance overlay stops at the display's rate, 60 on most screens. It does not tell how much room a game has left. The new top line answers that from the times the overlay measures. - possibleFps in src/editor/frameMeter.ts is 1000 ms over the sum of the five areas, rounded down. It has no number while nothing took any time, and the overlay shows a dash then. - The editor's share is in the sum, because it costs time while playing in the editor. A released game can do a little better. - It is an upper bound. The GPU's time is not measured and not in it. - e2e 59e reads the lines one further down and checks the new line against the times it measured itself. Tests: - Unit frame-meter: 11 passed (+2 for possibleFps) - Gate: 197 files, 2855 tests, CHECK EXIT 0 (2853 + 2) - e2e 59: ALL PASSED, 19 checks (+1), on melektaus-atx - Counter-check: possibleFps without the editor's share fails the unit test - The e2e total of 1602 is counted (1601 + 1), not measured Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>