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In IE, I can say to not use a proxy when the ip adress is: 10.*

If I do the same in Firefox it doesn't work. It uses the proxy when I access a 10.** site.

How can I make Firefox don't use the proxy with a mask like IE?

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migrated from Oct 19 '11 at 11:20

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I've found the answer, but I didn't want to use a proxy addon.. – aF. Oct 19 '11 at 9:50
up vote 1 down vote accepted

10.1/999 is not a sensible IP range. I am answering this because at some point this will stop working if firefox validates the IP ranges better in the future. It is possible that 10.1/999 is not matching all of the 10 subnet anyway.

To exclude all of the range, use

The 8 means "match any address where the first 8 bits are the same". As an IP address is comprised of 4 x 8 bit octets, 8 means the first octet.

So the following 

means "match the first two octets" and so would match I

So it follows that 10.1/999 is meaningless. It is saying match the first 999 bits of Given that an IP address is only 32 bits long, it is likely that this is working through a bug rather than intended behaviour.

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thanks m8! How can I exclude the following in firefox: * – aF. Oct 20 '11 at 8:57 Note the preceding dot. – Paul Oct 20 '11 at 10:36
yes, for example:,, etc.. How can I mask these? – aF. Oct 20 '11 at 13:46
The in the exclusions list means * would only exclude the main domain. – Paul Oct 20 '11 at 22:18

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