There was an interesting post on this subject here
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In order to make these changes you will first need to find your Firefox Profile.
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1. Find your Firefox profile
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If you are running Firefox 2 this is an easy matter as you can use the Extension Open Profile Folder
Go Tools/Open Profile Folder and you should see the Firefox Profile that you are running.
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If you cannot use Open Profile Folder you will have to look manually for your Firefox Profile Folder.
The following chart should help you locate your Firefox Profile:
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So once you have found the Firefox Profile.
Go
Extensions
install.rdf
and Edit RDF File
In this line you will see the current Version you are running.
1.90
If you change the value to a higher number than any current Version, you will no longer be prompted for updates
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related post:
How to return to Fast Dial 1.x after running Fast Dial 2.x
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