All the time when your install some new add-on in Firefox, you noticed that a small window display on your browser screen and notify you, waiting for some seconds.
But if you don’t want to wait, use this simple trick.
Type in your location bar – about:config
You will see a message – Click on I’ll be careful, I promise
Then in the filter bar type – security.dialog_enable_delay
Double click on security.dialog_enable_delay and set value 0 (By default value is 2000)
Restart your Firefox, now you can install add-on without wasting time.
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