Fixed a bug where a resumed recording wouldn't update the image Part 2

app/capture.js

@@ -24,6 +24,7 @@ const { encodePng } = require('../core/png');
 
 const CLICK_DEBOUNCE_MS = 700;
 const CLICK_CAPTURE_CACHE_MS = 75;
+const CLICK_CAPTURE_CACHE_MAX_AGE_MS = 400;
 const CLICK_CAPTURE_HIDE_DELAY_MS = 25;
 
 function hasBinary(name) {
@@ -257,9 +258,13 @@ class CaptureService {
     try {
       const mode = this.settings.get('capture.mode') || 'fullscreen';
       const grabMode = mode === 'region' ? 'fullscreen' : mode;
-      const cached = trigger === 'click' && this.captureCache && this.captureCache.mode === grabMode
-        ? this.captureCache
-        : null;
+      // The background refresh loop (startClickCaptureCache) keeps this
+      // updated every ~75ms; if it's gone stale (refresh errors silently and
+      // stops updating, or the cache was never refreshed after a resume),
+      // fall back to a fresh shot rather than reusing an old background.
+      const cacheFresh = this.captureCache && this.captureCache.mode === grabMode
+        && Date.now() - this.captureCache.capturedAt <= CLICK_CAPTURE_CACHE_MAX_AGE_MS;
+      const cached = trigger === 'click' && cacheFresh ? this.captureCache : null;
       const finalResult = cached
         ? this.storeFrameAsStep(this.session.guideId, grabMode, cached, clickPos)
         : await this.shoot({

docs/CHANGELOG.md

@@ -92,10 +92,12 @@ Initial release.
   literal text "undefined" by an old bug); a corrupted file is now
   treated as empty instead of crashing the dialog, and is overwritten
   with valid JSON the next time settings are saved.
-- Resuming a paused capture session no longer reuses the same stale
-  background screenshot for every click capture (only the click marker
-  moved); pausing now fully resets the click-capture cache so resuming
-  starts a fresh background refresh loop.
+- Click captures no longer reuse the same stale background screenshot
+  for every step (only the click marker moved). Pausing now fully resets
+  the click-capture cache so resuming starts a fresh background refresh
+  loop, and a cached frame older than 400ms (e.g. if the background
+  refresh silently stops working) is now discarded in favor of a fresh
+  screenshot.
 
 ### Added (initial feature set)
 

tests/unit/capture.test.js

@@ -143,6 +143,33 @@ test('click-triggered capture marks the click-time cursor position, not the cach
   assert.ok(Math.abs(marker.y - (0.5 - (d * 120 / 80) / 2)) < 1e-9);
 });
 
+test('click-triggered session capture falls back to a fresh shot when the cached frame is stale', async () => {
+  const service = makeService();
+  service.session = { guideId: 'guide-stale', paused: false, count: 0, intervalSec: 0 };
+  // A frame that's well past the cache's max age — e.g. the background
+  // refresh loop died (errored silently, or never restarted after a
+  // pause/resume) and left a frozen, increasingly-stale frame behind.
+  service.captureCache = {
+    mode: 'fullscreen',
+    png: Buffer.from('stale-png'),
+    size: { width: 120, height: 80 },
+    display: { bounds: { x: 0, y: 0, width: 120, height: 80 } },
+    cursor: { x: 60, y: 40 },
+    capturedAt: Date.now() - 10_000,
+  };
+
+  let shootCalled = false;
+  service.shoot = async () => {
+    shootCalled = true;
+    return { ok: true, step: { stepId: 'fresh-step' } };
+  };
+
+  const result = await service.sessionCapture('click', { x: 1, y: 1 });
+
+  assert.equal(result.ok, true);
+  assert.equal(shootCalled, true, 'a stale cached frame must not be reused');
+});
+
 test('live-shot click capture also marks the click-time cursor position', async () => {
   const service = makeService();
   service.settings.get = (key) => {