Impossible to set width in viewport less than 500px

[grafoxy]

I tried to set screenshot size with width 360px or 414px but it is impossible and for these cases Chrome set width to 500px.

my config:
config.services = [
[
'novus-visual-regression',
{
compare: new VisualRegressionCompare.Spectre({
url: testEnv.spectreUrl,
project: 'WEB',
suite: 'Visual regression testing',
test: function getTest(context) {
return context.test.title;
},
browser: function getBrowser(context) {
return context.browser.name;
},
size: function getSize(context) {
return context.meta.viewport.width;
},
fuzzLevel: 30
}),
viewportChangePause: 3000,
viewports: [
{ width: 360, height: 640 },
{ width: 414, height: 736 },
{ width: 640, height: 480 }
],
}
]
];

Is it possible to make screenshots with a width less than 500px, maybe some workarounds?