Startups times shouldn't be longer due to update. Perhaps cache is too big. Go to menu -> Settings -> Privacy & security -> Cookies & site data -> press the Clear data button.

Your screenshot shows that you're using uBlock Origin along with AdBlock+. Seriously: Do NOT use similar-purposed blocker(s) along with uBlock Origin: this will cripple uBO's ability to defuse anti-blocker mechanisms and its ability to minimize likelihood of site breakage. ("similar-purposed" = any other blocker making use of EasyList). uBlock Origin is enough.

Actually, there are two of them:

0: {name: Adblock Plus - free ad blocker, type: extension, version: 4.2, isActive: TRUE, id: {d10d0bf8-f5b5-c8b4-a8b2-2b9879e08c5d}}
1: {name: AdBlocker Ultimate, type: extension, version: 3.8.25, isActive: TRUE, id: adblockultimate@adblockultimate.net}

You also have several password manager extensions and several download extensions.

Firefox 115 ESR only gets security updates that shouldn't have effect on startup speed.

Does this still happen if you disable the VPN?

Start Firefox in Troubleshoot Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration or if userChrome.css/userContent.css is causing the problem.

• switch to the Default System theme: "3-bar" menu button or Tools -> Add-ons -> Themes
• do NOT click the "Refresh Firefox" button on the Troubleshoot Mode start window

• https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode
• https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

there is no vpn and the cache clear. I did not ask for comments on installed extensions, everything was fine until recent updates. Firefox 115 ESR only gets security updates that shouldn't have effect on startup speed; But In Fact it did change the startup speed. Firefox always load faster without extensions, I have tried disabling the extension one by one, I cannot blame the slow startup on extension since they have not changed in years only Firefox change with an update and slow speed.

I see this extension in your System Details...

{name: Browsec VPN - Free VPN for Firefox, type: extension, version: 3.84.1, isActive: TRUE, id: browsec@browsec.com}

To bad there is no objective way to test the Firefox first load time, as there is for webpages; suggestion often have nothing to do with the answers. once load after 10 second now all the other pages load timely; it is only the first load taking 10 seconds now.

the vpn is not being used, so please stop taking about it. the problem is the Firefox startup time, with the extensions, without the extension there is no reason to use Firefox.

You can try to uninstall (disable) the two ad-blocker extension I mention above and only leave UBO enabled as we have seen cases reported about Adblock Plus causing memory related issues.

To bad there is no objective way to test the Firefox first load time, as there is for webpages; suggestion often have nothing to do with the answers. once load after 10 second now all the other pages load timely; it is only the first load taking 10 seconds now.

I have already said I disable the extension with no changes in load time.

https://firefox-source-docs.mozilla.org/performance/reporting_a_performance_problem.html https://profiler.firefox.com/docs/#/./guide-getting-started https://profiler.firefox.com/ I found a test but I could not get it to work, it say cannot find profile, and cannot load profile in 30 seconds etc.

Can you post a similar screenshot with system info. see screenshot Did you already clear the startup cache? see screenshot

Well that is the third time suggested to clear the cache, that does not make any difference. Firefox ESR has been work great until 115.12 and of course security updates can be an issue. Without any changes on my part Firefox went for starting up in one second to 12 seconds. It would seem the update slowed the loading of extension some how, but I am not removing them they have a use; unlike Firefox starting up in 12 second that is not useful anymore. It starts faster without the extensions, but so what, Firefox is not useful without the extension and Chrome has the same extension and no startup issues.

It is a problem if there is no object way to tell what the problem is.

This is a different cache that I didn't see mentioned before.

I file a bug, since this is not helping.

Open Bug 1904165 Opened 9 minutes ago Updated 1 minute ago

slow startup on first open Firefox ESR 115.12