Filter on an external email account?

[ScottChapman]

It seems that filters do not apply to external email accounts?

I set up an external POP3 email account, but it appears that I cannot create filters that apply to it.

Is that by design?

[phoenix]

That's correct, you can't currently apply filters on external accounts. There's an RFE in bugzilla to change that behaviour, if you wish to vote on it.