From 6de443e833cdba634806c2d7e52310526a230da3 Mon Sep 17 00:00:00 2001
From: mitchross <mitchross@users.noreply.github.com>
Date: Thu, 26 Mar 2026 00:29:06 -0400
Subject: [PATCH] Fix clock flickering from duplicate setInterval timers

app.js and nav.html both started 1-second intervals updating the same
#headerUtcTime element. Even though both used InterceptTime, their
slightly different timing caused visible text flicker.

Fix: app.js now sets window._navClockStarted before starting its
interval, so nav.html's guard condition skips its duplicate. Also
register InterceptTime.onChange listener in app.js for instant updates.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---
 static/js/core/app.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/static/js/core/app.js b/static/js/core/app.js
index 7734f5f..ffc3c04 100644
--- a/static/js/core/app.js
+++ b/static/js/core/app.js
@@ -465,7 +465,11 @@ function initApp() {
     // Start clock and init time settings
     initTimeSettings();
     updateHeaderClock();
+    window._navClockStarted = true;  // Prevent nav.html from starting a duplicate interval
     setInterval(updateHeaderClock, 1000);
+    if (typeof InterceptTime !== 'undefined' && InterceptTime.onChange) {
+        InterceptTime.onChange(updateHeaderClock);
+    }
 
     // Load bias-T setting
     loadBiasTSetting();