A great idea, I have now implemented this in a new version 1.0.5, you can install now :).

Just fyi you cannot supply your own ranges due to how extensions are compiled, but the option page now shows which ips it matches for.

const HOSTNAMES = ['fritz.box', 'fritz.nas'];

const IP_RANGES = {
'192.168.0.x': [
'192.168.0.1',
'192.168.0.2',
'192.168.0.3',
'192.168.0.4',
'192.168.0.5',
'192.168.0.6',
'192.168.0.7',
'192.168.0.8',
'192.168.0.9',
'192.168.0.10'
],
'192.168.1.x': [
'192.168.1.1',
'192.168.1.2',
'192.168.1.3',
'192.168.1.4',
'192.168.1.5',
'192.168.1.6',
'192.168.1.7',
'192.168.1.8',
'192.168.1.9',
'192.168.1.10'
],
'192.168.178.x': [
'192.168.178.1',
'192.168.178.2',
'192.168.178.3',
'192.168.178.4',
'192.168.178.5',
'192.168.178.6',
'192.168.178.7',
'192.168.178.8',
'192.168.178.9',
'192.168.178.10'
]
};