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Firefox slowed to a crawl after updating Norton Security.

  • 4 replies
  • 1 has this problem
  • 15 views
  • Last reply by cor-el

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Updated to latest version of Norton. FF hung up ("not responding" msg) every time a new tab was opened. Refreshed FF; now tabs work fine, but FF is extremely slow. Pages that used to takt one second or less to load now take from two to ten minutes.

Updated to latest version of Norton. FF hung up ("not responding" msg) every time a new tab was opened. Refreshed FF; now tabs work fine, but FF is extremely slow. Pages that used to takt one second or less to load now take from two to ten minutes.

Chosen solution

You can check for problems with the places.sqlite database file (bookmarks, history) in the Firefox profile folder.

If the Places Maintenance extension can't repair the places.sqlite database file then remove all places.sqlite file(s) in the Firefox profile folder to make Firefox rebuild the places.sqlite database file from the most recent JSON backup in the bookmarkbackups folder.

You can check for problems with the sessionstore.js file in the Firefox profile folder that stores session data. When sessionstore.js is deleted you lose App Tabs and Tab Groups and open tabs and you will have to recreate them, so if necessary make a note or bookmark them.

You can use this button to go to the current Firefox profile folder:

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In the Add-ons Manager, on the left, select Extensions.

Some added toolbar and anti-virus add-ons are known to cause Firefox issues. Disable All of them.

Restart Firefox.

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Thanks, but there are no add-ons to disable. Problem persists.

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FredMcD said

toolbar and anti-virus add-ons
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Chosen Solution

You can check for problems with the places.sqlite database file (bookmarks, history) in the Firefox profile folder.

If the Places Maintenance extension can't repair the places.sqlite database file then remove all places.sqlite file(s) in the Firefox profile folder to make Firefox rebuild the places.sqlite database file from the most recent JSON backup in the bookmarkbackups folder.

You can check for problems with the sessionstore.js file in the Firefox profile folder that stores session data. When sessionstore.js is deleted you lose App Tabs and Tab Groups and open tabs and you will have to recreate them, so if necessary make a note or bookmark them.

You can use this button to go to the current Firefox profile folder: