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Every time I open FF & before I can do ANYTHING, it gives me a button to press, while saying something about javascript "missing = in xml attribute".

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  • Last reply by cor-el

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I can't do anything in firefox until I press the button, and the button keeps popping up every single time I open ff, even after deleting it and redownloading it, turning my computer off and on again, etc etc.

I can't do anything in firefox until I press the button, and the button keeps popping up every single time I open ff, even after deleting it and redownloading it, turning my computer off and on again, etc etc.

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It is possible that there is a problem with the files sessionstore.js and sessionstore.bak in the Firefox Profile Folder.

Delete the sessionstore.js file and possible sessionstore-##.js files with a number and sessionstore.bak in the Firefox Profile Folder.

Deleting sessionstore.js will cause App Tabs and Tab Groups and open and closed (undo) tabs to get lost, so you will have to create them again (make a note or bookmark them).


Try to clear the cache and the cookies.

"Clear the Cache":

  • Firefox > Preferences > Advanced > Network > Cached Web Content: "Clear Now"

"Remove Cookies" from sites causing problems or all cookies if you can't identify the domain:

  • Firefox > Preferences > Privacy > Cookies: "Show Cookies"