Slow web GUI in Firefox
Posted: Tuesday 21 July 2026 11:37
Hi,
Version: v2026.2
Platform: Windows 11 (Domoticz server and browser web GUI)
Plugin/Hardware: PC, x64, multiple machines
Description:
I noticed that especially web GUI (https) starts and also usage later is very slow when using Firefox v152.0.6 with previously registered service worker, meaning 2nd and subsequent starts. Chrome does not seem to suffer from this problem.
Here is example how to 100% reproduce the problem:
1. first url access in Domoticz url in Firefox is immediate, only few ms
2. 2nd and all subsequent url access takes around 6 seconds
3. when only service worker is unregistered (F12 options), then 1st run is again immediate, while 2nd and subsequent are slow again
Slowness is actually not limited to first url access, but also later in navigation - although difference is much smaller, not nearly as big as 6 second for start. Due to to described problem i strongly believe problem is in the service worker - either code itself or some sort of compatibility problems with problems related to Firefox alone. It could also be code problem, but Chrome somehow tolerates it, who knows.
Problems seems to appear only for HTTPS, not HTTP. HTTPS is using self signed certificates, while self signed CA is added to Windows certificate store, so connection is shown as trusted.
Version: v2026.2
Platform: Windows 11 (Domoticz server and browser web GUI)
Plugin/Hardware: PC, x64, multiple machines
Description:
I noticed that especially web GUI (https) starts and also usage later is very slow when using Firefox v152.0.6 with previously registered service worker, meaning 2nd and subsequent starts. Chrome does not seem to suffer from this problem.
Here is example how to 100% reproduce the problem:
1. first url access in Domoticz url in Firefox is immediate, only few ms
2. 2nd and all subsequent url access takes around 6 seconds
3. when only service worker is unregistered (F12 options), then 1st run is again immediate, while 2nd and subsequent are slow again
Slowness is actually not limited to first url access, but also later in navigation - although difference is much smaller, not nearly as big as 6 second for start. Due to to described problem i strongly believe problem is in the service worker - either code itself or some sort of compatibility problems with problems related to Firefox alone. It could also be code problem, but Chrome somehow tolerates it, who knows.
Problems seems to appear only for HTTPS, not HTTP. HTTPS is using self signed certificates, while self signed CA is added to Windows certificate store, so connection is shown as trusted.